Mulder, Iris, Raymond van der Meer, Han de Vries, and Elisabeth H M Sterck. “The Effect of a Diet Change on Regurgitation and Reingestion in Captive Chimpanzees”. Journal of Zoo and Aquarium Research 4, no. 4 (November 3, 2016): 196–201. Accessed March 29, 2025. https://jzar.org/jzar/article/view/185.