“Metal Contents and Acute Toxicity of Combined Vernonia Amygdalina Leaves and Garcinia Kola Seeds-VAGK, a Herbal and Nutritional Formulation in Male Wistar Rats”. African Journal of Biomedical Research, vol. 22, nº 2, maio de 2019, p. 187-94, https://ojshostng.com/index.php/ajbr/article/view/2260.