Coto, Cesar, S. Cerate, Z. Wang, F. Yan, Y. Min, F.P. Costa, and P.W. Waldroup. 2010. “Effect of Source and Level of Vitamin D on the Performance of Breeder Hens and the Carryover to the Progeny”. International Journal of Poultry Science 9 (7): 623–633. https://doi.org/10.3923/ijps.2010.623.633.