Kozlowski, Corinne P, et al. “Patterns of Fecal Steroids Associated With Reproduction in Two Cracidae Species: The Blue-Throated Piping Guan (Pipile Cumanensis Cumanensis) and the Horned Guan (Oreophasis Derbianus)”. Journal of Zoo and Aquarium Research, vol. 6, no. 3, July 2018, pp. 85-90, doi:10.19227/jzar.v6i3.351.