Pereira, E.F. da C. et al. 2014. Outbreak of Newcastle disease in Rio Grande do Sul (Brasil) caused by contamined fowlpox vaccine. Pesquisa Agropecuaria Brasileira. 8, 6 (Apr. 2014), 31–33. DOI:https://doi.org/10.1590/S1678-3921.pab1973.v8.17352.