LAWAL, A.; MOHAMMED, S.; DAMISA, D. Assessment of levels of copper, cadmium and lead in secretion of mammary gland of cows grazed on open fields. Science World Journal, [S. l.], v. 1, n. 1, 2010. DOI: 10.4314/swj.v1i1.51689. Disponível em: https://www.ajol.info/index.php/swj/article/view/51689. Acesso em: 17 oct. 2026.