List of Articles Quasi-fixed inputs Open Access Article Abstract Page Full-Text 1 - Estimation of Returns to Scale in the Presence of Undesirable (bad) Outputs in DEA when the Firm is Regulated F .Emami M .Rostamy malkhalifeh H .Safdari Open Access Article Abstract Page Full-Text 2 - An Additive Model for Estimation Return to Scale in Regulated Environment with Quasi-Fixed Inputs in Data Envelopment Analysis (DEA) Farshid Emami Toktam Nasirzade Tabrizi