@article{article65c19554,
title   = {Petrographic approach to the study of organic microfossils from the Irati Subgroup (Permian, Paraná Basin, Brazil)},
author = {Calça, Cleber Pereira and Fairchild, Thomas R.},
year = {2012},
doi = {10.1016/j.jsames.2011.10.005},
journal   = {Journal of South American Earth Sciences}
}