@article{AA_2017_29_3_a3,
     author = {G. Panina},
     title = {Oriented area is a~perfect {Morse} function},
     journal = {Algebra i analiz},
     pages = {61--69},
     publisher = {mathdoc},
     volume = {29},
     number = {3},
     year = {2017},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AA_2017_29_3_a3/}
}