M., Farooq., M.A. Mian, Zahoor- ul-Haq, F.R. Durrani, and M. Syed. 2002. “Standardizing Limits for Cost of Production in Commercial Egg Operation”. International Journal of Poultry Science 1 (6): 179–184. https://doi.org/10.3923/ijps.2002.179.184.