The Liquid-Liquid Extraction of Toxic Metals (Cd, Hg and Pb) by Calixarenes. Pakistan Journal of Analytical & Environmental Chemistry, Pakistan, v. 10, n. 1 & 2, p. 1–13, 2009. DOI: 10.21743/. Disponível em: https://pjaec.pk/index.php/pjaec/article/view/436. Acesso em: 12 jul. 2025.