S., Garba, et al. “Immunomodulatory Effects of Neem (Azadirachta Indica) Leaf Aqueous Extracts in Cockerels Vaccinated and Experimentally Infected With Infectious Bursal Disease Virus”. International Journal of Sciences: Basic and Applied Research (IJSBAR), vol. 37, no. 2, Feb. 2018, pp. 72-89, https://gssrr.org/JournalOfBasicAndApplied/article/view/8348.