Detection of antibodies against hepatitis a virus in eluates of blood spotted on filter-paper - Almeida, L. M; Azevedo Neto, Raymundo Soares de; Guimarães, A. M. A; Coutinho, E. S. F; Struchiner, C. J; Massad, Eduardo (Congresso Brasileiro de Epidemiologia, 1998)