List of Articles dual-role factor Open Access Article Abstract Page Full-Text 1 - Time-staged outputs in production process: A DEA-Based Approach S. Seyedboveir M. Maghbouli F. Matrood Open Access Article Abstract Page Full-Text 2 - Cost Efficiency of Closed–Loop Supply Chain in the Presence of Dual-Role and Undesirable Factors M. Jahani Sayyad Noveiri S. Kordrostami A.R. Amirteimoori