Study the optical characteristics of polystyrene polymer before and after doping with methyl orange. Periodicals of Engineering and Natural Sciences, [S. l.], v. 9, n. 4, p. 368–374, 2021. DOI: 10.21533/pen.v9.i4.950. Disponível em: https://pen.ius.edu.ba/index.php/pen/article/view/950. Acesso em: 18 apr. 2026.