Correa, Jamille de Souza, et al. “Purification and Characterization of Colophony Extracted of Pinus Elliottii (Engelm, Var. Elliottii)”. Orbital: The Electronic Journal of Chemistry, vol. 10, no. 3, May 2018, pp. 200-3, https://periodicos.ufms.br/index.php/orbital/article/view/16345.