@inproceedings{inproceedings051613a2,
title   = {Oscillating and periodic solutions of equation of type 'X 2 PONTOS'+f1 (x)'X PONTO'+f2 (x)'X PONTO POT.2+G' (x) =0},
author = {Guidorizzi, Hamilton L.},
year = {1991},
publisher = {ICMC-USP},
booktitle   = {Seminário Brasileiro de Análise}
}