%0 Journal Article %A Gelbukh, Irina %T Morse-Bott functions with two critical values on a surface %J Czechoslovak Mathematical Journal %D 2021 %P 865-880 %V 71 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.21136/CMJ.2021.0125-20/ %R 10.21136/CMJ.2021.0125-20 %G en %F 10_21136_CMJ_2021_0125_20