Nali, Luiz Henrique da Silva, et al. “High Prevalence of the Simultaneous Excretion of Polyomaviruses JC and BK in the Urine of HIV-Infected Patients Without Neurological Symptoms in São Paulo, Brazil”. Revista Do Instituto De Medicina Tropical De São Paulo, vol. 54, no. 4, Aug. 2012, pp. 201-5, https://revistas.usp.br/rimtsp/article/view/48390.