González-Hein, Gisela A., Carlos M. González, y Bernardo R. Huaracán. 2017. «Fatal Dual Infection of Avian Polyomavirus and Psittacine Beak and Feather Disease Virus in Chile». Austral Journal of Veterinary Sciences 49 (1):59-61. http://revistas.uach.cl/index.php/australjvs/article/view/729.