Alvarenga, F. da C. L. e. Ultrastructural Differences Between Leydig Cells of Horses: Asses and Hinnies. Braz. J. Vet. Res. Anim. Sci. 1992, 29 (2), 173-180. https://doi.org/10.11606/issn.1678-4456.bjvras.1992.51981.