C. M. Korndörfer, C. F. Meirelles, I. C. da S. Bueno, and A. L. Abdalla, “Evaluation of extraction methods for progesterone determination in rabbit (Oryctolagus cuniculus) feces by radioimmunoassay”, Braz. J. Vet. Res. Anim. Sci., vol. 35, no. 3, pp. 115–119, Jan. 1998, doi: 10.1590/S1413-95961998000300004.