@article{SM_1975_25_3_a6,
     author = {A. V. Kochergin},
     title = {On mixing in special flows over a~shifting of segments and in smooth flows on surfaces},
     journal = {Sbornik. Mathematics},
     pages = {441--469},
     publisher = {mathdoc},
     volume = {25},
     number = {3},
     year = {1975},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1975_25_3_a6/}
}