Investigation of sewage contamination using steroid indexes in sediments of the Guajará Estuary (Amazon coast, Brazil) - Gomes, Heyde Gonçalves; Kawakami, Silvia Keiko; Taniguchi, Satie; Souza Filho, Pedro Walfir M; Montone, Rosalinda Carmela (Brazilian Journal of Oceanography, 2015)