ZHENG, H.L.; FAN, W.; XIE, W.Y.; JI, F.Y.; TAN, M.Z.; YANG, C. Catalytic Spectrophotometric Determination of Ultra Trace-level Copper(II) with Indigo Carmine. Asian Journal of Chemistry, [S. l.], v. 25, n. 17, p. 9547–9550, 2013. DOI: 10.14233/ajchem.2013.15068. Disponível em: https://asianpubs.org/index.php/ajchem/article/view/25_18_28. Acesso em: 29 mar. 2024.