NAKSEN, P.; SAISUI, P. .; CHOMPHU, T. .; CHAKSUMA, W. .; ANUTRASAKDA, W. .; JARUJAMRUS, P. Barcode-like paper sensor for water hardness detection. Journal of Science and Science Education (JSSE), [S. l.], v. 4, n. 1, p. 51–61, 2021. Disponível em: https://so04.tci-thaijo.org/index.php/JSSE/article/view/251650. Acesso em: 13 apr. 2025.