SOROKA, Yu. Yu. Homeotopy groups of rooted tree like non-singular foliations on the plane. Methods of Functional Analysis and Topology, [S. l.], v. 22, n. 3, p. 283–294, 2016. Disponível em: https://zen.imath.kiev.ua/index.php/mfat/article/view/642. Acesso em: 16 dec. 2025.