L. E. Velázquez Rosas, C. Fregoso Aguayo, R. López Ordaz, and J. Hernández Cerón, “Estrous response and conception rate in postpartum Bos taurus-Bos indicus cows, treated with bovine somatotropin in an ovulation induction program with progestogens and eCG”, Vet Mex OA, vol. 42, no. 3, Jul. 2013.