Fava, Claudia Del, et al. “Occurrence of Seropositive Sheep (Ovis Aries) to Bovine Leukemia Virus in Brazil”. Brazilian Journal of Veterinary Research and Animal Science, vol. 47, no. 6, Dec. 2010, pp. 483-7, https://doi.org/10.11606/issn.1678-4456.bjvras.2010.26811.