Articles in Peer Reviewed Journals

If you are interested in obatining any articles, please contact Professor Joe Zhu.


121. Gong, Y., Zhu, Joe, Chen, Y., and Cook, W.D., DEA as a tool for auditing: Application to Chinese manufacturing industry with parallel network structures, Annals of Operations Research, (in press)
120. Li, W.H., Liang, L., Aviles-Sacoto, S., Imanirad, R., Cook, W.D., and Zhu, Joe, Modeling efficiency in the presence of multiple partial input to output processes, Annals of Operations Research, (in press)
119. Cook, W.D., Du, J., and Zhu, Joe, Units invariant DEA when weight restrictions are present: Ecological performance of US electricity industry Annals of Operations Research, (in press)
118. Miller, F., Wang, J., Zhu, Joe, Chen, Y., and Hockenberry, J., Investigation of the impact of the Massachusetts health care reform on hospital costs and quality of care, Annals of Operations Research, (in press)
117. Chen, Y., Cook, W.D., Du, J., Hu, H. and Zhu, Joe, Discrete and bounded data and Likert scales in data envelopment analysis: Application to regional energy efficiency in China, Annals of Operations Research (in press),
116. Li, H., Chen, C-L, Cook, W.D., Zhang, J., and Zhu, Joe, Two-stage network DEA: Who is the leader? OMEGA (in press),
115. Wu, J., Zhu, Q.Y., Cook, W.D., and Zhu, Joe, Best cooperative partner selection and input resource reallocation using DEA, Journal of the Operational Research Society (in press),


114. Guo, C. and Zhu, Joe, Non-cooperative two-stage network DEA model: Linear vs. parametric linear, European Journal of Operational Research, Vol. 258, Issue 1 (2017), 398-400.
113. Guo, C., Abbasi Shureshjani, R., Foroughi, A. and Zhu, Joe, Decomposition weights and overall efficiency in two-stage additive network DEA, European Journal of Operational Research, Vol. 257, Issue 3 (2017), 896-906.
112. Cook, W.D., Ruiz, J.L., Sirvent, I. and Zhu, Joe, Within-group common benchmarking using DEA, European Journal of Operational Research, Vol. 256, Issue 3 (2017), 901-910.


111. Du, J., Huo, J-Z, and Zhu, Joe, Data envelopment analysis with output-bounded data, Asia-Pacific Journal of Operational Research, Vol. 33, Number 6 (2016), 1650050 [17 pages].
110. Li, W, Liang, L., Cook, W.D., and Zhu, Joe, DEA models for non-homogeneous DMUs with different input configurations, European Journal of Operational Research, Vol. 254, Issue 3 (2016), 946-956.
109. Shwartz, M., Burgess, J.F. Jr, and Zhu, Joe, A DEA based composite measure of quality and its associated data uncertainty interval for health care Provider profiling and pay-for-performance, European Journal of Operational Research, Vol. 253, Issue 2 (2016), 489-502.
108. Lim, S., and Zhu, Joe, A note on two-stage network DEA model: frontier projection and duality, European Journal of Operational Research, Vol. 248. Issue 1 (2016), 342-346.


107. Aviles-Sacoto, S., Cook, W.D., Imanirad, R., and Zhu, Joe, Two-stage network DEA: When intermediate measures can be treated as outputs from the second stage, Journal of the Operational Research Society, Vol. 66, Issue 11 (2015), 1868-1877.
106. Imanirad, R., Aviles-Sacoto, S., Cook, W.D., and Zhu, Joe, Partial input to output impacts in DEA: The case of DMU-specific impacts, European Journal of Operational Research, Vol. 244, Issue 3 (2015), 837-844.
105. Du, J., Zhu, Joe, Cook, W.D., and Huo, J-Z, DEA models for parallel systems: game-theoretic approaches, Asia-Pacific Journal of Operational Research, Vol. 32, No. 2 (2015), 1550008 (22 pages).
104. Lim, S., and Zhu, Joe, DEA Cross-efficiency evaluation under variable returns to scale, Journal of the Operational Research Society, Vol. 66, Issue 3 (2015), 476-487.


103. Du, J., Wang, J., Chen, Y., Chou, S-Y, and Zhu, Joe, Incorporating health outcomes in Pennsylvania hospital efficiency: An additive super-efficiency DEA approach, Annals of Operations Research, Vol. 221, Issue 1 (2014), 161-172.
102. Park, J., Lee, D., and Zhu, Joe, An integrated approach for ship block manufacturing process performance evaluation: Case from a Korean shipbuilding company, International Journal of Production Economics, Vol. 156 (2014), 214-222.
101. Lim, S., Oh, K.W., and Zhu, Joe, Use of DEA cross-efficiency evaluation in portfolio selection: an application to Korean stock market, European Journal of Operational Research, Vol. 236 (2014), 361-368.
100. Du, J., Cook, W.D., Liang, L., and Zhu, Joe, Fixed cost and resource allocation based on DEA cross-efficiency, European Journal of Operational Research, Vol. 235 (2014), 206-214.
99. Cook, W.D., and Zhu, Joe, DEA Cobb-Douglas frontier and cross-efficiency, Journal of the Operational Research Society, Vol. 65, Issue 2 (2014), 265-268.
98. Cook, W.D., Tone, K., and Zhu, Joe, Data envelopment analysis: Prior to choosing a model, OMEGA, Vol. 44 (2014), 1-4.
97. Sahoo, Biresh K., Zhu, Joe, Tone, K., and Klemen, B.M., Decomposing technical efficiency and scale elasticity in two-stage network DEA, European Journal of Operational Research, Vol. 233, Issue 3 (2014), 584-594.


96. Cook, W.D., Harrison, J., Imanirad, R., Rouse, P., and Zhu, Joe, Data envelopment analysis with non-homogeneous DMUs, Operations Research, Vol. 61, No. 3 (2013), 666-676.
95. Lim, S., and Zhu, Joe, Incorporating performance measures with target levels in data envelopment analysis, European Journal of Operational Research, Vol. 230, Issue 3 (2013), 634-642. [Corrigendum EJOR, Vol. 231, Issue 3 (2013), p 790.]
94. Sherman, H.D., and Zhu, Joe, Analyzing performance in service organizations, Sloan Management Review, Vol. 54, No. 4 (Summer 2013), 36-42. [translated and published: Analizar el desempeño en organizaciones de servivio, Harvard Deusto business review, No. 228 (2013), 6-15.]
93. Imanirad, R., Cook, W.D., and Zhu, Joe, Partial input to output impacts in DEA: Production considerations and resource sharing among business sub-units, Naval Research Logistics, Vol. 60, Issue 3 (2013), 190-207.
92. Lim, S., and Zhu, Joe, Integrated data envelopment analysis: Global vs local optimum, European Journal of Operational Research, Vol. 229, Issue 1 (2013), 276-278.
91. Chen, Y., Cook, W.D., Kao, C., and Zhu, Joe, Network DEA pitfalls: Divisional efficiency and frontier projection under general network structures, European Journal of Operational Research, Vol. 226 (2013), 507-515.


90. Premachandra, I.M., Zhu, Joe, Watson, J., and Galagedera, D.U.A., Best-performing US mutual fund families from 1993 to 2008: Evidence from a novel two-stage DEA model for efficiency decomposition, Journal of Banking and Finance, Vol. 36, Issue 12 (2012), 3302-3317.
89. Chen, C-M, Du, J. Huo, J., and Zhu, Joe, Undesirable factors in integer-valued DEA: Evaluating the operational efficiencies of city bus systems considering safety records, Decision Support Systems, Vol. 54 (2012), 330-335.
88. Chen, C-L, Zhu, Joe, Yu, J-Y, and Noori, H., A new methodology for evaluating sustainable product design performance with two-stage network data envelopment analysis, European Journal of Operational Research, Vol. 221, Issue 2 (2012), 348-259.
87. Cook, W.D., Harrison, J., Rouse, P., and Zhu, Joe, Relative efficiency measurement: The problem of a missing output in a subset of decision making units, European Journal of Operational Research, Vol. 220, Issue 1 (2012), 79-84.
86. Du, J., Chen, C-M, Chen, Y., Cook, W.D., and Joe Zhu, Joe, Additive super-efficiency in integer-valued data envelopment analysis, European Journal of Operational Research, Vol. 218 (2012), 186-192.
85. Lee, H-S, and Zhu, Joe, Super-efficiency infeasibility and zero data in DEA, European Journal of Operational Research, Vol. 216 (2012), 429-433.


84. Cook, W.D., and Zhu, Joe, Multiple variable proportionality in data envelopment analysis, Operations Research, Vol. 59, No. 4 (2011), 1024-1032.
83. Cook, W.D., and Zhu, Joe, Output-specific input-assurance regions in DEA, Journal of the Operational Research Society, Vol. 62 (2011), 1881-1887.
82. Zhu, Joe, Airlines performance via two-stage network DEA approach, Journal of CENTRUM Cathedra, Vol. 4, Issue 2 (2011), 260-269.
81. Chen, C-M, and Zhu, Joe, Efficient resource allocation via efficiency bootstraps: An application to R&D project budgeting, Operations Research, Vol. 59 (2011), May-June, pp. 729-741.
80. Lee, H-S, Chu, C-W, and Zhu, Joe, Super-efficiency DEA in the presence of infeasibility , European Journal of Operational Research, Vol. 212 (2011), 141-147.
79. Liang, L., Li, Z-Q, Cook, W.D., and Zhu, Joe, Data envelopment analysis efficiency in two-stage networks with feedback, IIE Transactions, Vol. 43 (2011), 309-322.
78. Du, J., Liang, L., Chen, Y., Cook, W.D., and Zhu, Joe, A bargaining game model for measuring performance of two-stage network structures, European Journal of Operational Research, Vol. 210, Issue 2 (2011), 390-397.


77. Cook, W.D., Zhu, Joe, Bi, G-B, and Yang, F., Network DEA: Additive efficiency decomposition, European Journal of Operational Research, Vol. 207, Issue 2 (2010), 1122-1129.
76. Chen, Y., Du, J., Sherman, H.D., and Zhu, Joe, DEA model with shared resources and efficiency decomposition, European Journal of Operational Research, Vol. 207 (2010), 339-349.
75. Cook, W.D., Liang, L., and Zhu, Joe, Measuring performance of two-stage network structures by DEA: A review and future perspective, OMEGA, Vol. 38 (2010), 423-430.
74. Cook, W.D., and Zhu, Joe, Context-dependent performance standards in DEA, Annals of Operations Research, Vol. 173, No. 1 (2010), 163-175.
73. Du, J., Liang, L., and Zhu, Joe, A slacks-based measure of super-efficiency in data envelopment analysis: A Comment, European Journal of Operational Research, Vol. 204 (2010), 694-697.
72. Chen, Y., Cook, W.D., and Zhu, Joe, Deriving the DEA frontier for two-stage processes, European Journal of Operational Research, Vol. 202 (2010), 138-142.


71. Cook, W.D., and Zhu, Joe, Piecewise linear output measures in DEA, European Journal of Operational Research, Vol. 197 (2009), 312-319.
70. Cook, W.D. Yang, F., and Zhu, Joe, Nonlinear inputs and diminishing marginal value in DEA, Journal of the Operational Research Society, Vol. 60, No. 11 (2009), 1567-1574.
69. Chen, Y., Cook, W.D., Li, N., and Zhu, Joe, Additive efficiency decomposition in two-stage DEA, European Journal of Operational Research, Vol. 196 (2009), 1170-1176.
68. Cook, W.D., Liang, L., Zha, Y., and Zhu, Joe, A modified super-efficiency DEA model for infeasibility, Journal of the Operational Research Society, Vol. 69 (2009), 276-281.
67. Chen, Y., Liang, L., and Zhu, Joe, Equivalence in two-stage DEA approaches, European Journal of Operational Research, Vol. 193 (2009), Issue 2, 600-604.


66. Liang, L., Wu, J., Cook, W.D., and Zhu, Joe, The DEA game cross efficiency model and its Nash equilibrium, Operations Research, Vol. 56, No. 5 (2008), 1278-1288.
65. Liang, L., Cook, W.D., and Zhu, Joe, DEA Models for two-stage processes: Game approach and efficiency decomposition, Naval Research Logistics, Vol. 55 (2008), 643-653.
64. Liang, L., Wu, J., Cook, W.D., and Zhu, Joe, Alternative secondary goals in DEA cross-efficiency evaluation, International Journal of Production Economics, Vol. 113 (2008), 1025-1030.
63. Cook, W.D., and Zhu, Joe, CAR-DEA: Context-dependent assurance regions in DEA, Operations Research, Vol. 56, No. 1 (2008), 69-78.
62. Cooper, W.W., Huang, Z., Li, S., and Zhu, Joe, A response to the critiques of DEA by Dmitruk and Koshevoy, and Bol, Journal of Productivity Analysis, Vo. 29, No. 1 (2008), 15-21.


61. Cooper, W.W., Seiford, L.M., Tone, K., and Zhu, Joe, Some models and measures for evaluating performances with DEA: Past accomplishments and future prospects, Journal of Productivity Analysis, Vol. 28, No. 3 (2007), 151-163.
60. Gregorious, G.N., and Zhu, Joe, Data envelopment analysis – a way to assess the efficiency of funds of hedge funds, Journal of Portfolio Management, Vol. 33, No. 2 (2007), 120-132.
59. Cook, W.D., and Zhu, Joe, Classifying inputs and outputs in data envelopment analysis, European Journal of Operational Research, Vol. 180, Issue 2 (2007), 692-699.
58. Cook, W.D., and Zhu, Joe, Within-group common weights in DEA: An analysis of power plant efficiency, European Journal of Operational Research, Vol. 178, Issue 1 (2007), 207-216.


57. Sherman, D.H., and Zhu, Joe, Benchmarking with quality-adjusted DEA (Q-DEA) to seek lower-cost high-quality service: Evidence from a U.S. bank application, Annals of Operations Research, Vol. 145, No. 1 (2006), 301-319.
56. Liang, L., Yang, F. Cook, W.D., and Zhu, Joe, DEA models for supply chain efficiency evaluation, Annals of Operations Research, Vol. 145, No. 1 (2006), 35-49.
55. Cook, W.D., and Zhu, Joe, Preface for the Special Issue on “Performance Evaluation and Beyond: Data Envelopment Analysis Research Frontiers” in Honor of William W. Cooper, Annals of Operations Research, Vol. 145, No. 1 (2006), 1-3.
54. Cook, W.D., and Zhu, Joe, Rank order data in DEA: A general framework, European Journal of Operational Research, Vol. 174, Issue 2 (2006), 1021-1038.
53. Cook, W.D., and Zhu, Joe, Incorporating multiprocess performance standards into the DEA framework, Operations Research, Vol. 54, No. 4 (2006), 656-665.
52. Cook, W.D. Green, R.H., and Zhu, Joe, Dual-role factors in data envelopment analysis, IIE Transactions, Vol. 38, Number 2 (2006), 105-115.
51. Chen, Y., Liang, L., Yang, F., and Zhu, Joe, Evaluation of information technology investment: A data envelopment analysis approach, Computers & Operations Research, Vol. 33, Issue 5 (2006), 1368-1379.


50. Chen, Y., Morita, H., and Zhu, Joe, Context-dependent DEA with an application to Tokyo public libraries, International Journal of Information Technology and Decision Making, Vol. 4, No. 3 (2005), 385-394.
49. Huang, Z.M., Li, S.X., and Zhu, Joe, A Special Issue on “Data Envelopment Analysis: Theories and Applications” in honor of William W. Cooper, International Journal of Information Technology and Decision Making, Vol. 4, No. 3 (2005), 311-316.
48. Seiford, L.M., and Zhu, Joe, Notes on sensitivity and stability of the classifications of returns to scale in data envelopment analysis: A comment, Journal of Productivity Analysis, Vol. 23, No. 3 (2005), 315-316.
47. Morita, H., Hirokawa, K., and Zhu, Joe, A slack-based measure of efficiency in context-dependent data envelopment analysis, OMEGA, Vol. 33, Issue 4 (2005), 357-362.
46. Cook, W.D., and Zhu, Joe, Allocation of shared costs among decision making units: A DEA approach, Computers & Operations Research, Vol 32, Issue 8 (2005), 2171-2178.
45. Cook, W.D., and Zhu, Joe, Building performance standards into data envelopment analysis structures, IIE Transactions, Vol 37, Issue 3 (2005), 267-275.
44. Gregoriou, G.N., Sedzro, K., and Zhu, Joe, Hedge fund performance appraisal using data envelopment analysis, European Journal of Operational Research, Vol. 164, Issue 2 (2005), 555-571.
43. Seiford, L.M., and Zhu, Joe, A response to comments on modeling undesirable factors in efficiency evaluation, European Journal of Operational Research, Vol. 161, Issue 2 (2005), 579-581.


42. Cook, W.D., Seiford, L.M., and Zhu, Joe, Models for performance benchmarking: Measuring the effect of e-business activities on banking performance, OMEGA, Vol. 32, Issue 4 (2004), 313-322.
41. Zhu, Joe, Imprecise DEA via standard linear DEA models with a revisit to a Korean mobile telecommunication company, Operations Research, Vol. 52, No. 2 (2004), 323-329.
40. Chen, Y., and Zhu, Joe, Measuring information technology’s indirect impact on firm performance, Information Technology & Management Journal, Vol. 5, Issue 1-2 (2004), 9-22.
39. Banker, R.D., Cooper, W.W., Seiford, L.M., Thrall, R.M., and Zhu, Joe, Returns to scale in different DEA models. European Journal of Operational Research, Vol. 154, Issue 2 (2004), 345-362.
38. Zhu, Joe, A buyer-seller game model for selection and negotiation of purchasing bids: extensions and new models, European Journal of Operational Research, Vol. 154, Issue 1 (2004), 150-156.


37. Mistry, J.J., and Zhu, Joe, Strategic and transactional use of information technology in banking. The Journal of Cost Analysis & Management, Volume 5, Issue 2, (2003), 1-22.
36. Chen, Y., and Zhu, Joe, DEA Models for Identifying critical performance measures, Annals of Operations Research, Vol.124, No. 1-4 (2003), 225-244.
35. Morita, H., and Zhu, Joe, Models for characterizing and measuring supply chain efficiency and achieving best practice. System, Control and Information, Vol. 16, No. 8, (2003), 388-396. (in Japanese 森田浩, J ZHU, サプライチエインの効率性の測定と最適化のためのモデル, システム制御情報学会論文誌.)
34. Chen, Y., Morita, H., and Zhu, Joe, Multiplier bounds in DEA via strong complementary slackness condition solution, International Journal of Production Economics, Vol. 86, No. 1, (2003), 11-19.
33. Seiford, L.M., and Zhu, Joe, Context-dependent data envelopment analysis-- measuring attractiveness and progress. OMEGA, Vol. 31, Issue 5, (2003), 397-480. [Note: Computational errors have been discovered in the paper. However, they do not affect the results. These errors are corrected in Cook and Zhu, Designing and Modeling Performance Evaluation Issues, Springer Science, 2005.]
32. Cook, W.D., and Zhu, Joe, Output deterioration with input reduction in data envelopment analysis, IIE Transactions, Vol. 35, No. 3, (2003), 309-320.
31. Johnson, S.A., and Zhu, Joe, Identifying “best” applicants in recruiting using data envelopment analysis, Socio-Economic Planning Sciences, Vol. 37, Issue 2 (2003), 125-139.
30. Zhu, Joe, Efficiency evaluation with strong ordinal input and output measures, European Journal of Operational Research, Vol. 146, Issue 3 (2003), 477-485.
29. Zhu, Joe, Imprecise data envelopment analysis (IDEA): A review and improvement with an application, European Journal of Operational Research, Vol. 144, Issue 3 (2003), 513-529.


28. Seiford, L.M., and Zhu, Joe, Value judgment versus allocative efficiency: a case of Tennessee county jails, Journal of Management Sciences & Regional Development, Issue 4, July (2002), 89-98.
27. Li, S.X., Huang, Z.M., Zhu, Joe, and Chau, P.Y.K., Cooperative advertising, game theory and manufacturer-retailer supply chains, OMEGA, Vol.30, Issue 5 (2002), 347-357.
26. Seiford, L.M., and Zhu, Joe, Modeling undesirable factors in efficiency evaluation, European Journal of Operational Research, Vol. 142, Issue 1 (2002), 16-20.


25. Zhu, Joe, A multidimensional quality-of-life measure with an application to Fortune’s best cities, Socio-Economic Planning Sciences, Vol. 35, Issue 4 (2001), 263-284.
24. Cooper, W.W., Seiford, L.M., and Zhu, Joe, Slacks and congestion: response to a comment by R. Fare and S. Grosskopf, Socio-Economic Planning Sciences, Vol. 35, Issue 3 (2001), 205-215.
23. Wilkens, K., and Zhu, Joe, Portfolio evaluation and benchmark selection: A mathematical programming approach, Journal of Alternative Investments, Vol. 4, No. 1, Summer, (2001), 9-19.
22. Cooper, W.W., Li, S., Seiford, L.M., Tone, K., Thrall, R.M., and Zhu, Joe, Sensitivity and stability analysis in DEA: some recent developments, Journal of Productivity Analysis, Vol. 15, No. 3 (2001), 217-246.
21. Zhu, Joe, Super-efficiency and DEA sensitivity analysis. European Journal of Operational Research, Vol. 129, Issue 2 (2001), 443-455.[Erratum, EJOR, Volume 179, Issue 1, (2007), Page277.]


20. Zhu, Joe, Further discussion on linear production functions and DEA. European Journal of Operational Research, Vol. 127, Issue 3 (2000), 611-618.
19. Zhu, Joe, Setting scale efficient targets in DEA via returns to scale estimation method. Journal of the Operational Research Society, Vol. 51, No. 3 (2000), 376-378.
18. Zhu, Joe, Multi-factor performance measure model with an application to Fortune 500 companies. European Journal of Operational Research, Vol. 123, Issue 1, (2000), 105-124.
17. Cooper, W.W., Seiford, L.M., and Zhu, Joe, A unified additive model approach for evaluating inefficiency and congestion with associated measures in DEA. Socio-Economic Planning Sciences, Vol. 34, Issue 1 (2000), 1-25.


16. Seiford, L.M., and Zhu, Joe, Profitability and marketability of the top 55 US commercial banks. Management Science, Vol. 45, No. 9 (September 1999), 1270-1288.
15. Seiford, L.M., and Zhu, Joe, Infeasibility of super-efficiency data envelopment analysis models. INFOR, Vol. 37, No. 2, (May 1999), 174-187.
14. Seiford, L.M., and Zhu, Joe, Sensitivity and stability of the classification of returns to scale in data envelopment analysis. Journal of Productivity Analysis, Vol. 12, No. 1, (1999), 55-75.
13. Seiford, L.M., and Zhu, Joe, An investigation of returns to scale in data envelopment analysis. OMEGA, Vol. 27, No. 1 (1999), 1-11.


12. Seiford, L.M., and Zhu, Joe, Sensitivity analysis of DEA models for simultaneous changes in all the data. Journal of the Operational Research Society, Vol. 49, No. 10 (1998), 1060-1071.
11. Zhu, Joe, Data envelopment analysis vs. principal component analysis: An illustrative study of economic performance of Chinese cities. European Journal of Operational Research, Vol. 111, Issue 1, (1998), 50-61.
10. Seiford, L.M., and Zhu, Joe, On alternative optimal solutions in the estimation of returns to scale in DEA. European Journal of Operational Research, Vol. 108, No. 1, (1998) 149-152.
9. Seiford, L.M., and Zhu, Joe, Stability regions for maintaining efficiency in data envelopment analysis. European Journal of Operational Research, Vol. 108, Issue. 1, (1998), 127-139.
8. Seiford, L.M., and Zhu, Joe, Identifying excesses and deficits in Chinese industrial productivity (1953-1990): A weighted data envelopment analysis approach. OMEGA, Vol. 26, No. 2 (1998), 279-296.
7. Ray, S.C., Seiford, L.M., and Zhu, Joe, Market entity behavior of Chinese state-owned enterprises. OMEGA, Vol. 26, No. 2 (1998), 263-278.
6. Seiford, L.M., and Zhu, Joe, On piecewise loglinear frontiers and log efficiency measures. Computers and Operations Research, Vol. 25, No. 5, (1998), 389-395.
5. Seiford, L.M., and Zhu, Joe, An acceptance system decision rule with data envelopment analysis. Computers and Operations Research, Vol. 25, No. 4, (1998), 329-332.


4. Zhu, Joe, DEA/AR analysis of the 1988-1989 performance of the Nanjing Textile Cooperation. Annals of Operations Research, Vol. 66, (1996), 311-335.
3. Zhu, Joe, Robustness of the efficient DMUs in data envelopment analysis. European Journal of Operational Research, Vol. 90, Issue 3 (1996), 451-460.
2. Zhu, Joe, Data envelopment analysis with preference structure. Journal of the Operational Research Society, Vol. 47, No.1 (1996), 136-150.
1. Zhu, Joe, and Shen, Z.H., A discussion of testing DMUs' returns to scale. European Journal of Operational Research, Vol. 81, Issue 3 (1995), 590-596.