Sánchez Riquelme, A., and M. De los Reyes Solovera. “Zona Pellucida: An Extracellular Matrix With Applications in the Study of Immunocontraception in Domestic Carnivores”. Revista Científica De La Facultad De Ciencias Veterinarias, Vol. 14, no. 5, 1, http://www.produccioncientifica.luz.edu.ve/index.php/cientifica/article/view/15077.