@article{article0bf611a7,
title   = {Megaspores from coals of the Triunfo Member, Rio Bonito Formation (Lower Permian), northeastern Paraná State, Brazil},
author = {Ricardi-Branco, Frésia and Arai, Mitsuru and Rösler, Oscar},
year = {2002},
doi = {10.1590/s0001-37652002000300011},
journal   = {Anais da Academia Brasileira de Ciências}
}