Robust non-parametric regression models for some petroleum products. Periodicals of Engineering and Natural Sciences, [S. l.], v. 8, n. 1, p. 263–271, 2020. DOI: 10.21533/pen.v8.i1.1045. Disponível em: https://pen.ius.edu.ba/index.php/pen/article/view/1045. Acesso em: 13 may. 2026.