Heavy metals in untreated/treated urban effluent and sludge from a biological wastewater treatment plant - Oliveira, Aline da Silva; Bocio, Ana; Trevilato, Tânia Maria Beltramini; Takayanagui, Angela Maria Magosso; Domingo, José L.; Segura-Muñoz, Susana Inés (Environmental Science and Pollution Research International, 2006)