KUZNIETSOVA, I. V.; SOROKA, Yu. Yu. The first Betti numbers of orbits of Morse functions on surfaces. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 73, n. 2, p. 179–200, 2021. DOI: 10.37863/umzh.v73i2.2383. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2383. Acesso em: 7 apr. 2025.