MAKOWSKA, D.; WIEROŃSKA, F. Analysis of content of selected critical elements in fly ash. GeoScience Engineering, [S. l.], v. 62, n. 1, p. 31–36, 2016. Disponível em: https://geoscience.cz/ojs/index.php/GSE/article/view/101. Acesso em: 30 apr. 2026.