ELEUCH, H.; ROTTER, I. EXCEPTIONAL POINTS IN OPEN AND PT-SYMMETRIC SYSTEMS. Acta Polytechnica, [S. l.], v. 54, n. 2, p. 106–112, 2014. DOI: 10.14311/AP.2014.54.0106. Disponível em: https://ojs.cvut.cz/ojs/index.php/ap/article/view/2078. Acesso em: 4 may. 2024.