J. P. G. de Lacerda, E. F. de L. Vieira, B. S. Martins, L. S. Giusti, and J. . Soares-Sobrinho, “Isolation of poliovirus obtained from cerebrospinal fluid of children with poliomyelitis”, Rev Inst Adolfo Lutz, vol. 33, no. 1-2, pp. 29–33, Dec. 1973.