Coutinho, J. M. V.; Hachiro, J. Distribution, Mineralogy, Petrography, Provenance and Significance of Permian Ash-Carrying Deposits in the Paraná Basin . Geol. USP. Sér. Cient. 2005, 5 (1), 29-39. https://doi.org/10.5327/S1519-874X2005000100003.