@inproceedings{inproceedings3616dcea,
title   = {Origin of ultra high energy cosmic rays},
author = {Medina Tanco, Gustavo Adolfo and Horvath, Jorge Ernesto and Gouveia dal Pino, Elisabete Maria de},
year = {1995},
publisher = {SBF/Inpe},
booktitle   = {Encontro Brasileiro de Física dos Plasmas}
}