@article{article1bed0014,
title   = {Protobranch bivalves from the Piauí formation (middle Pennsylvanian), Parnaíba basin, Brazil},
author = {Anelli, Luiz Eduardo and Rocha-Campos, A. C. and Simões, Marcello Guimarães},
year = {2002},
journal   = {Revista Española de Paleontología}
}