Perozo, Francisco, Giovanny Finol, y Yaneth Mavárez. 1. «Levels of immunoglobulin”“A in Trachea, Gut and Bile Samples of Chickens Vaccinated Against Newcastle Disease». Revista Científica De La Facultad De Ciencias Veterinarias 17 (3). http://195.26.248.148/index.php/cientifica/article/view/15279.