Asli, M.M. et al. 2007. Effect of Probiotics, Yeast, Vitamin E and Vitamin C Supplements on Performance and Immune Response of Laying Hen During High Environmental Temperature. International Journal of Poultry Science. 6, 12 (Nov. 2007), 895–900. DOI:https://doi.org/10.3923/ijps.2007.895.900.