Sial, A. N. “THE TERTIARY ALKALlNE PROVINCE OF FORTALEZA, STATE OF CEARÁ, BRAZIL: OXYGEN ISOTOPES ANO REE-GEOCHEMISTRY”. Geochimica Brasiliensis, vol. 1, no. 1, Apr. 2011, pp. 41-51, https://geobrasiliensis.emnuvens.com.br/geobrasiliensis/article/view/2.