List of Articles Additive model Open Access Article Abstract Page Full-Text 1 - Efficiency and Return to Scale of Two-Stage network in Data Envelopment Analysis Using Additive Model Mahboobeh Joghataie Farhad Hosseinzadeh lotfi Tofigh Allahviranloo Open Access Article Abstract Page Full-Text 2 - Ranking Efficient DMUs Using the Ideal point and Norms B. Shavazipour Open Access Article Abstract Page Full-Text 3 - Using MOLP based procedures to solve DEA problems P. Zamani F. Hosseinzadeh Lotfi