@article{VMUMM_2009_4_a2,
     author = {E. A. Kudryavtseva},
     title = {Uniform {Morse} lemma and isotopy criterion for {Morse} functions on surfaces},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {13--22},
     publisher = {mathdoc},
     number = {4},
     year = {2009},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_2009_4_a2/}
}