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ISSN : 1598-7248 (Print)
ISSN : 2234-6473 (Online)
Industrial Engineering & Management Systems Vol.18 No.1 pp.67-77
DOI : https://doi.org/10.7232/iems.2019.18.1.067

A Systematic Literature Review on Lean Office

Tamie Takeda Yokoyama*, Marco Aurélio de Oliveira, André Hideto Futami
Department of Production Engineering, University Center, Educational Society of Santa Catarina, Joinville, Brazil
Corresponding Author, E-mail: engprod.edu@gmail.com
September 14, 2017 July 15, 2018 January 15, 2019

ABSTRACT


With the increasing competition in the market, organizations have sought solutions to improve their operational performance. In this context, the application of the Lean Manufacturing principles has increased, also extending to nonmanufacturing areas, such as offices, where it received the name Lean Office (LO). The objectives of this research were to identify what are the main difficulties in LO implementations, propose a classification system and sort the collected literature. This research covered a period of study from the appearance of the first article on LO (2005), until the year before the end of this review (2016). It is methodologically characterized as systematic literature review, theoretical, exploratory, with qualitative and quantitative approach. The findings of this paper show that main difficulties encountered in the LO implementations are related to technical and cultural areas. This paper provides a better knowledge of LO literature, a LO implementations profile, and valuable support for new researches in this area.



초록


    1. INTRODUCTION

    The business world has been changed by globalization as well as the meaning of value of a product to customers. Thus, companies have been operating in volatile and highly complex environments. The expectations of customers allied to increased competition require companies to know how to gain competitive advantage. There are different approaches to guide business in this new direction, such as the lean production system (Aguado et al., 2013;Azadegan et al., 2013;Pakdil and Leonard, 2014).

    It has been a while since lean principles were recognized as a way to gain competitive advantage. Therefore, in order to improve operational performance, lean practices have been ever more implemented by companies (Azadegan et al., 2013;Pakdil and Leonard, 2014).

    Lean production brought a reflection about manufacturing and service operations not only of the repetitive production environment, and also changed the trade-off between quality and productivity. It can be said that, in this way, it has satisfactorily challenged the practices of mass production (Holweg, 2007).

    Lean manufacturing is a set of techniques that can reduce and eliminate wastes, making the companies more flexible and responsive. With lean philosophy, in the end, the processes can run using fewer materials, people and inventory, requiring less investment, and consuming less space (Wilson, 2009).

    The lean manufacturing’s techniques, tools and principles can be applied in various industry segments, enabling waste elimination in order to achieve operational excellence. Originally, its principles were applied only on manufacturing sectors, because it was developed in this area. Subsequently, its application was spread to other productive areas, where there exists a scope for process improvement (Davim, 2015).

    There has been an increase in the number of manufacturers who recognize that to have a true Lean transformation its principles must be applied to all company operations, not being restricted to the shop floor (Productivity Press Development Team, 2005). Therefore, it has become more frequent use lean in other areas, for example in administrative environments.

    It is called Lean Office (LO) the implementation of lean manufacturing philosophy in offices and administrative processes. LO helps to streamline information flow in any administrative function, focusing on reducing the total cycle time (Wang, 2010). To Davim (2015), companies can only experience the process improvements and benefits of lean manufacturing principles if its implementation is successful. Thus, the objectives of this research carried out through a systematic literature review was to identify the main difficulties in the LO implementations, propose a classification system and sort the collected literature. This study is important for better knowledge of the literature – because there is very limited literature that discusses the LO –, to present a profile of the application of LO, and to suggest researches to find methodologies and solutions for making successful implementations.

    To better understand the research, this paper is organized as follows: Section 2 presents the research methodology; Section 3 presents the description and analysis of results, explaining the statistics about LO publications, the main difficulties in LO implementation, and a classification system for this literature. Finally, in Section 4 are exposed the final considerations of the research.

    2. METHODOLOGY

    In this section, we present the research classification and the necessary steps for its development. We also clarified the criteria for searching and collecting articles (manuscripts), as well as the dimensions analyzed in this review.

    2.1 Research Classification, Steps and Search Criteria

    This scientific work was conducted through a systematic literature review. A systematic review has a clearly stated purpose, defined search approach and question research, explicitly stated criteria for inclusion and exclusion from the study, and produces a qualitative appraisal of articles (Jesson et al., 2011). The use of this approach is justified by allowing the view of practical and conceptual knowledge and its updating as soon as new researches are done (Gough et al., 2012).

    The research is classified as an exploratory study according to its purpose. Exploratory research is one that aims to explore and to question the object of study to identify what is happening (Gray, 2016).

    The sequence of steps required for the development of this research is illustrated in Figure 1. It is important to report that once defined the steps 1 to 3, this systematic literature review can be carried out again, at other times, with the same search criteria, identifying new contributions and changes to the studied area.

    In the step 1, the research objectives were defined. They were presented in the introduction of this article. In the step 2, it was delimited the area to search articles: engineering and management. In the step 3, in order to obtain a wide coverage of the literature, a large number of scientific databases (platforms) were selected, totaling 13: Academic Search Premier – ASP (EBSCO); Compendex (Engineering Village); Emerald Insight (Emerald); IEEE Xplore; Open Access Library; SciELO.ORG; Science Direct (Elsevier); SCOPUS (Elsevier); Springer Link; Scientific Open Access Repositories of Portugal (RCAAP); Technology Research Database (ProQuest); Web of Science (Thomson Reuters Scientific); Wiley Online Library.

    These databases provide access to international scientific literature, they work with a wide-ranging of journals, providing electronic storage for scientific articles from various fields (multidisciplinary). To collect only articles aligned with the research theme, the strategy was to find articles with the keywords “lean office” and “lean AND office” in the title, abstract, or keywords, as shown Table 1. To increase the accuracy, following filters were selected and applied: a) engineering and management as subject or area of study; b) English as language (to cover worldwide publications); c) academic articles (reviewed) of journals, magazines or conferences as document type. Filters “a” to “c” were applied together, or those that were available in the databases. A period of coverage (years) has not been delimited to reach more comprehensive view of the literature on the subject from the outset.

    In the step 4, using the selected filters, it was made a search of articles in the databases, finding a total of 960 articles (occurrences). In the step 5, a brief reading of the titles and abstract of these articles was done within the databases, to verify if they met the research theme. In this way, a total of 632 articles were excluded, and a total of 328 articles were collected. In the step 6, after collected articles, reference management software was used to exclude duplicated articles. Then, the full texts of the articles were read in order to ensure a relevant articles portfolio to this review, i.e., articles that address the topic LO or have objectives related to this research area. Therefore, articles that only had the word “lean office” in the abstract and did not attempt to research directly in this topic were excluded. At the end of this step, a total of 19 articles were analyzed, with a publication date between 2005 and 2016.

    In the step 7, it was developed a classification system for collected literature. Finally, in the step 8, the LO literature was sorted and the results of all research are presented in the following sections.

    2.2 Dimensions of Analysis

    The selected articles were analyzed and classified according to 6 parameters: type of research; research performance; main activity of the organizations; lean tools; findings and main difficulties.

    In terms of the type of research, papers were categorized according to its research purpose into the following types:

    • (AN) Analytical or Explanatory: It is based on theory to try to answer ‘how’ and ‘why’ to research questions, in other words (i.e.), it uses the theory or at least tests hypotheses to try to explain the reasons that cause the studied phenomenon (Cooper and Schindler, 2013).

    • (DE) Descriptive: It aims to describe or define the research object, and for this, usually creates a profile of the issue, problem, subject or event to be studied. It may involve collecting data, creating a distribution of the number of times that the research variable is observed by the researcher, or establishing the relationship of the interaction of two or more variables. This type of research is not concerned with explaining the reason why variables interact in the manner that they do or why an event occurred (Cooper and Schindler, 2013).

    • (EX) Exploratory: Your goal is to find ideas and patterns and develop hypotheses. It seeks to gain greater familiarity with the subject area so at a later step do a more rigorous investigation. Generally, it has an open approach and uses extensive data and impression collection and rarely provides conclusive answers to questions or problems, but provides guidance for conducting future research. An example of techniques used is case study, historical analysis and observation (Collis and Hussey, 2013).

    • (PR) Predictive: Based on hypotheses and general relations, and through analysis, the predictive research seeks generalization, predicting certain phenomena. Thus, if predictive research presents a valid and robust solution, it is possible to apply this solution from a particular problem to similar problems, including predicting the likelihood of a similar situation occurring elsewhere (Collis and Hussey, 2013).

    According to research performance, papers were classified into the following categories:

    • (Pl) Practical: those described LO implementations, LO tools application, include data collecting or another management practices.

    • (Tl) Theoretical: those were based on LO literature reviews, game or simulation, conceptual frameworks, or case studies without LO implementation.

    Regarding the main activity of the organizations under study in the selected papers, the classification was made according to an adaptation of the major groups of the Standard Industrial Classification (SIC) system:

    • (A) Agriculture, forestry and fishing;

    • (B) Construction;

    • (C) Finance, Insurance and Real State;

    • (D) Manufacturing;

    • (E) Mining;

    • (F) Not classifiable (non-operating establishments);

    • (G) Not applicable (no organization studied or no described);

    • (H) Public administration;

    • (I) Retail trade;

    • (J) Services (health, educational, hotels, engineering, accounting, research, management, laboratories, consulting, technology);

    • (K) Transportation, communications, electric, gas and sanitary service;

    • (L) Wholesale trade;

    Regarding the area of the organization:

    (a) Private;

    (b) Public;

    (c) Not applicable (no organization studied);

    In terms of the Lean tools, an adaptation of the LO tools presented by Tapping and Shuker (2003) was made and a code was created for each one, as follows:

    • (1) 5S;

    • (2) Buffer resources;

    • (3) Continuous flow (one-piece flow);

    • (4) FIFO lanes;

    • (5) Heijunka;

    • (6) Kanban and/or Pull system;

    • (7) Line balancing (workload balance);

    • (8) No LO tools (other tools were used);

    • (9) Not described or not applied (implementation was made, but information was omitted);

    • (10) Not applicable (works that did not involve implementation or are theoretical);

    • (11) Pitch (visual management);

    • (12) Runners;

    • (13) Safety resources;

    • (14) Standardized work;

    • (15) Supermarkets;

    • (16) Takt time;

    • (17) U-shaped work areas (layout change);

    • (18) Value stream mapping;

    The last classification for LO literature was created to explore the main difficulties and challenges encountered in LO implementations. It is composed of 4 categories:

    • (CD) Cultural Difficulties: Difficulties or challenges involving cultural, behavioral factors, e.g. resistance to change, cultural differences, problems of cooperation and dedication, lack of interest, lack of commitment;

    • (PD) Difficulties with lack of Parameters or technical difficulties: Involves challenges or difficulties of being able to identify and/or measure, activities, tasks, value streams due to lack of parameters or technical ability or experience. It also covers the difficulty in using work tools and the lack of data, indicators and control.

    • (FD) Financial Difficulties: Here are categorized the difficulties or challenges due to factors such as lack of money, or the denial of using it for investments linked to lean implementation.

    • (KD) Difficulties with lack of Knowledge: This category covers the lack of knowledge about LO and lack of theoretical basis.

    3. DESCRIPTION AND ANALYSIS OF RESULTS

    The final screening process of this systematic review resulted in 19 articles that fulfilled the research refinement criteria and became its object of study. These papers came from publication in 15 different journals, as shown in Table 2.

    The 15 journals revealed that the research subject is mainly not addressed by special journals dedicated to the subject, but by journals in other related areas that also dealing tangentially with a discipline that encompasses Lean.

    The journals that most concentrate articles in LO area are Proceedings of IGLC (International Group for Lean Construction): Annual Conference of the International Group for Lean Construction and Quality: Access to Success (Calitatea), both with a total of 3 articles. Although the first journal is dedicated to Lean, it focuses on only one lean specialty, which involves its application in the civil construction field. The second periodical is not about Lean, but covers it, however, it is important to explain that the 3 articles found in this journal are from the same authors, being part of the same work.

    Otherwise, grouping articles by database according to decreasing amount of number of publications on LO, the result is shown in Table 3.

    This table covers the years of collected publications to provide a broader view of what has already been revised to guide future research. It should be noted that there was no time limit in the research.

    The total sum is greater than 19 because an article is found in more than one database, being counted for both.

    The database with more articles on the researched topic is Scopus, with 10 articles. This result does not diverge from that expected, since Scopus is considered the largest database, according to its website.

    The results of analyzed parameters and the classification of each article are presented and discussed in the following subsections.

    3.1 Literature Classification

    The presentation of literature classification on a given topic allows academic community and researchers to verify what has already been studied, by what methodology, in what environment and circumstances, with which tools, providing the possibility to find gaps or to improve researches. Table 4 shows the result of the classification of collected articles on LO, making it possible to obtain an overview of the main characteristics of the literature in the area.

    From this review and classification, in terms of the type of research, it was evident that the predictive research is under-explored in the area, having only 1 article characterized in this category. The most popular type with a total of 9 articles is the exploratory research, this fact can be probably due to its less rigorous nature.

    Regarding the research development, there is a predominance of practical research, with a difference of 1 article more than the theoretical research, which does not imply to be a trend. With respect to the place of research application – excluding 9 articles that are theoretical works and therefore do not occur in an environment of productive activities –, among 10 practical articles, 3 studied civil construction, 3 manufacturing, 2 services and 2 Transportation, communications, electric, gas and sanitary service. The corresponding area of these 10 articles was balanced between 5 works in the private area and 5 works in the public area.

    The most used and/or cited lean tool is 5S, present in 10 papers. Second is value stream mapping, present in 8 articles. In the third position is the standardized work cited in 6 articles, followed by continuous flow and pull system and/or kanban, both present in 5 articles each. The takt time tool appeared in 3 articles, and FIFO lanes, line balancing, U-shaped work areas appeared in 2 articles each. The other tools presented by Tapping and Shuker (2003) were not mentioned in any of collected articles and two articles not commented on any tool. The article of Kemmer et al. (2009) comments about the use of another type of tool instead of the traditional, they use a graphic tool, replacing the value stream mapping.

    Besides to specific LO tools described by Tapping and Shuker (2003), other tools classified in the selected papers as belonging to Lean and that can be used in the office environment were employed and/or cited. From Kuriger et al. (2010) and Mirehei et al. (2011), the following lean tools can be adapted and used in an office: Poka-yoke (errorproofing), elimination of over processing, multifunctional workforce, and total quality. From the second paper of Nãftãnãilã and Mocanu (2014b) following lean tools belong to administrative area: quality at the source, visual controls and management, mistake-proofing (Poka-yoke), people involvement, batch reduction or elimination, pull system, resource reliability, and cellular/teaming concepts.

    3.2 Statistics Publications on LO

    The selected articles allowed to verify that the term LO began to be present in publications from 2005. Figure 2 depicts this result as well as the distribution of the publications on LO in the last 12 years.

    The study of article publications series over time in-dicates that research in this area is likely to maintain the ratio of 1 published article per year. The justification for this is that the publications average during the 12 years is 1.5 publications per year, and the result of the correlation analysis between the two variables is R² = 0.29; this low value does not represent confirmation of the growing trend.

    Another consideration is that 2014 and 2015 may be considered outliers, but this can be verified from a longer time analysis that confirms the consistency of the ratio of 1 annual article. It is observed that among the four publications of 2014, three are from same authors, being part of one work, consequently, in that year, only two publications were made. Thus, if the two points (2014 and 2015) were the main responsible for generating the small growth trend and the very slight correlation, the hypothesis of growth tendency can be discarded.

    3.3 Main Findings in the LO Implementations

    This literature review showed that when LO imple-mentation occurs is limited mainly to one or a few de-partments or administrative processes of an organization, i.e. does not occur in all administrative departments, such as the articles of Chen and Cox (2012), Sabur and Simatupang (2015), Kemmer et al. (2009), Costa et al. (2013), Rossiti et al. (2016) and Jin and Kachroo (2010). Therefore, it represents 60% of the 10 articles that involved some practical type of implementation. In addition, it is common not to use all tools of LO toolbox presented by Tapping and Shuker (2003), but only use one or few tools (maximum 5), as observed in all articles of Table 4.

    Another characteristic that became evident is that LO implementation usually occurs after Lean manufacturing is already practiced in the company, especially in its area of origin – the shop floor (non-administrative). This is the case of articles of Chen and Cox (2012), Kemmer et al. (2009), Costa et al. (2013) and Huls (2005), who commented that lean was already used in studied organizations.

    The small number of articles found in this review reveals that the LO subject is still under-researched. Among the 19 articles, only 1, the article of Chen and Cox (2012) presents a methodology for implementing the LO, and 1, the article of Bodin (2013) explores and explains the LO types of approach, which according to authors are two, the neo-Tayloristic approach and the team-based approach. To previously guide LO implementation, the article of El-Akkad et al. (2007) provides criteria for categorizing offices. The categorization provides a better identification of the goals and responsibilities of each employee and brings the whole hierarchy closer to lean. Moreover, the benefits of applying lean in an office already categorized is an improved throughput time and greater overall performance (El-Akkad et al., 2007). These results show that currently there are few references to guide LO implementations to be successful.

    Through this review it was also possible to extract the main benefits of LO implementation, cited by more than one article each: lead time reduction (Costa et al., 2013;Rossiti et al., 2016;Sabur and Simatupang, 2015; The new improvement frontier: Developing lean administration, 2005;Monteiro et al., 2015); cost reduction (Chen and Cox, 2012; The new improvement frontier: Developing lean administration, 2005; Huls, 2005); reduction of time to perform activities (cycle time) (Costa et al., 2013;Rossiti et al., 2016;da Silva et al., 2015); reduction of activities that do not add value (Chen and Cox, 2012;da Silva et al., 2015); improvement in the behavior and well-being of the work team (Monteiro et al., 2015;Huls, 2005); Improvement in productivity (performance) (Costa et al., 2013;Monteiro et al., 2015); improvement in the quality of a product and/or service (Costa et al., 2013;Huls, 2005); better service and customer satisfaction (da Silva et al., 2015; The new improvement frontier: Developing lean administration, 2005).

    In addition, LO also provides work processes pulled by client (pull system) (Chen and Cox, 2012); Faster and systematic monitoring of tasks (Chen and Cox, 2012); Waste elimination (Costa et al., 2013), such as waiting times (Rossiti et al., 2016); Reduction of inventory to be processed (Kemmer et al., 2009); Reduction of rework (Huls, 2005); Faster response time (Huls, 2005); Adds value to tasks (Costa et al., 2013); More streamlined processes (Huls, 2005); Better use of office space (Monteiro et al., 2015); improved communication between team work (Huls, 2005); greater knowledge of activities and processes (Huls, 2005) and meet deadlines (Costa et al., 2013).

    Two articles present simulation games for the im-plementation of lean tools in the office. The benefit of using LO games is that in case of a real implementation of the tools, employees who participated in these types of games have more support and confidence to face difficulties that may arise (Kuriger et al., 2010). LO simulation games also contribute to a better understanding of lean concepts and tools, so it is an effective training tool for lean implementation (Mirehei et al., 2011).

    Regarding the use of LO tools, it was noticed that there is no agreement on the distinction between Lean tools used in manufacturing and Lean tools used in the office. However, Rüttimann et al. (2014) suggest that lean tools need to be adapted for LO and the development is in progress by authors. The salient benefit of using LO tools is that it makes employees present an advance in lean behaviour (Puvanasvaran et al., 2015).

    Concerning to what tool use first in LO implementations, there is no consensus. Nãftãnãilã and Mocanu (2014b) proposes that 5S must be the first step towards a LO because it allows visual management and provides quick responses to abnormalities. Already Monteiro et al. (2015) say that 5S should not be the first tool to use because although it is easy to apply and present visible changes for everyone in the company, the gains of 5S are difficult to quantify. This could generate unfavorable arguments, preventing the LO implementation. The authors indicate to begin LO implementation by value stream mapping. This alternative was effective in generating rapid im-provements and more motivation and involvement for everyone (Monteiro et al., 2015).

    3.4 Main Difficulties in the LO Implementations

    In order to fill a gap in the literature – there are no studies that systematically reviewed the main difficulties and challenges that can be faced in LO implementations and there is no categorization –, this subsection was created. It aims to guide future research.

    The classification of LO implementation difficulties was made separately from the general classification in Table 4 to facilitate understanding. Table 5 presents the results based on the classification methodology described in Section 2, only about articles that were possible to identify and extract the challenges and difficulties reported by authors.

    From this table, it is evident that most of the prob-lems in LO implementations are due to technical difficulties or lack of parameters (PD category). To help address these difficulties further researches are required, mainly showing how measurements are taken in cases of successful LO implementations. In addition, it is relevant that implementations be carried out by trained professionals, who have technical knowledge and experience, to avoid simple problems and convey greater trust and support to organizations.

    The second category with the greatest number of problems is the Cultural Difficulties (DC). To try to over-come these challenges, it would be important previous training and kaizen events, involving entire organization. As confirms Kuriger et al. (2010), it is very important that all employees of an organization learn about Lean concepts.

    The category of Difficulties with lack of knowledge (KD) obtained the third position in the number of prob-lems. For this category, beyond the training indicated in the previous category (DC), more comprehensive and detailed studies on LO are needed to support its imple-mentation.

    Finally, the category of Financial Difficulties (FD) presented the least amount of problem. An alternative to these difficulties is to do a financial planning indicating required resources to implement LO and expected returns, with the complement of statistical basis and successful real cases.

    4. CONCLUSIONS

    This research made a systematic literature review on LO, presenting an overview of carried out studies on the subject. From an initial sample of 960 articles, only 19 met the research criteria, including conference articles that have lower scientific rigor level. This small amount demonstrates that although general LP theme attracts a lot of research, the specific LO theme is still under-researched.

    In the review, several dimensions of LO implementations were investigated, including the following: major journals with publications on the topic, analysis of the number of publications over time, research methodology, place of application, area, main findings and difficulties. As a result, it was found that LO theme is recent, appeared in selected bases from 2005, less than 2 decades, thus is still in development. There is no clear indication of a growing trend of LO publications, unless some kind of stimulus be done. At the moment, it maintains a constancy of 1 article per year.

    The most common type of research has been the exploratory research, with practice technique. The Journals with the largest number of publications in the area is Proceedings of IGLC (International Group for Lean Construction): Annual Conference of the International Group for Lean Construction and Quality: Access to Success (Calitatea). A relevant fact is that both are not dedicated to the LO topic. About the predominance of the place and area of research application, there was a draw between manufacturing industry and civil construction, and of these, 50% are from the private area and 50% from the public area. In terms of articles contributions, it is summarized that before LO implementation is necessary to use simulations like games to prepare employees for changes and train them to better adapt to the new philosophy. There is still no consensus on which LO tool start using in an implementation.

    Regarding the most important difficulties of LO implementation, similar characteristics were found and from this, it was created 6 categories to make its classification. The category with the highest incidence of occurrences was Technical difficulties or lack of parameters (PD). Singles recommendations such as training, competent professionals, among others have been made, but there is a need for deeper research to address these challenges and promote successful implementations.

    Some gaps were found: the studies failed to present whether after implementation, the changes and the new management were maintained and for how long; it is not standard the detail of which tools were used and what the sequence they were inserted in the environment; some researches also omit the number of people who participated in the process, if there was external consulting, and the difficulties faced. There was also a lack of research showing who agreed with the project, whether top management was involved and whether there was any previous planning.

    The limitations of this research were: the review was based on articles in the area of engineering and management, that included the words LO together or not, in the title, abstract and keywords. Consequently, there may be other studies that have not been check by this review. The contribution of this research, from a comprehensive analysis, is a provision of useful information, showing the current status of literature and gaps on the LO to guide new researches.

    As a suggestion for future research we indicate researches that detail how implementations were conducted; that make comparisons between the implementations in offices of different areas; that check if there is an indication of what LO tool to start implementation according to the office sector; and that present possible solutions to the difficulties encountered in this review.

    ACKNOWLEDGEMENT

    Authors would like to thank the anonymous reviewers for their comments and expertise that greatly improved the manuscript.

    Figure

    IEMS-18-1-67_F1.gif

    Research steps through systematic literature review.

    IEMS-18-1-67_F2.gif

    Publications per year.

    Table

    Detailed search criteria

    Journal per database and number of papers per periodical

    Papers per database

    Classification of collected papers

    Classification of difficulties and challenges

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