NIKOGHOSYAN, Z. G. A Sharp Improvement of a Theorem of Bauer and Schmeichel. Mathematical Problems of Computer Science, [S. l.], v. 50, p. 15–34, 2021. DOI: 10.51408/1963-0017. Disponível em: http://mpcs.sci.am/index.php/mpcs/article/view/45. Acesso em: 4 may. 2024.