Martínez-Alfaro J, Meza-Sarmiento IS, Oliveira RDS. Singular levels and topological invariants of Morse--Bott foliations on non orientable surfaces. TMNA [Internet]. 2018 Jan. 8 [cited 2024 Jul. 22];51(1):183-21. Available from: https://apcz.umk.pl/TMNA/article/view/TMNA.2017.051