Eloy, Angela Maria Xavier, and Richard Rodway. 1999. “Central Action of the Naloxone on ß-Endorphins and Luteinizing Hormone (LH) in Ovariectomized and Hypoglicemic Ewes”. Brazilian Journal of Veterinary Research and Animal Science 36 (5): 253-57. https://doi.org/10.1590/S1413-95961999000500006.