Stewien KE, Barbosa V, Rosenburg CP. Immunity levels to poliomyelitis in a sample of school children from the city of S. Paulo, Brazil . Rev. saúde pública [Internet]. 1977 Jun. 1 [cited 2024 May 16];11(2):270-8. Available from: https://www.revistas.usp.br/rsp/article/view/22841