The effect of metakaolin and hybrid polymers on the microstructure of concrete. Periodicals of Engineering and Natural Sciences, [S. l.], v. 9, n. 1, p. 162–173, 2021. DOI: 10.21533/pen.v9.i1.721. Disponível em: https://pen.ius.edu.ba/index.php/pen/article/view/721. Acesso em: 8 oct. 2025.