Tapparo , A.F. et al. 2009. Apoptosis detection in embryonic chicken lymphoid tissues infected with attenuated very virulent infectious bursal disease virus (vvIBDV). Brazilian Journal of Veterinary Pathology. 2, 2 (Nov. 2009), 75–79. DOI:https://doi.org/10.24070/bjvp.1983-0246.002013.