PRZYBYŁO, S. Equivalential algebras with conjunction on the regular elements. Annales Universitatis Paedagogicae Cracoviensis Studia Mathematica, [S. l.], v. 20, p. 63–75, 2021. Disponível em: https://studmath.up.krakow.pl/article/view/8501. Acesso em: 19 jan. 2022.