RIEČANOVÁ, Z. Effect Algebras of Positive Self-adjoint Operators Densely Defined on Hilbert Spaces. Acta Polytechnica, Prague, Czech Republic, v. 51, n. 4, 2011. DOI: 10.14311/1412. Disponível em: https://ojs.cvut.cz/ojs/index.php/ap/article/view/1412. Acesso em: 8 apr. 2025.