Feizpour, M. A., Nayeb, S., & Salehi Firozabadi, G. "Firm Size and Productivity: Evidenced from New Entrants in the Iran's Other Non-Metallic Minerals Industry during the Third Development Plan", Journal of Economic Research (Tahghighat- E- Eghtesadi), 48, 3, 2013, 69–86. doi: 10.22059/jte.2013.35811