Effects of progestagens and prostaglandin analogues on ovarian function and embryo viability in sheep - Gonzalez-Bulnes, A; Veiga-Lopez, A; Garcia, P; Garcia-Garcia, RM; Ariznavarreta, C; Sanchez, MA; Tresguerres, JA; Cocero, MJ; Flores, JM (Theriogenology, 2005)