@article{MZM_1970_8_4_a4,
     author = {S. B. Katok},
     title = {Linear extensions of dynamic systems and the reducibility problem},
     journal = {Matemati\v{c}eskie zametki},
     pages = {451--462},
     publisher = {mathdoc},
     volume = {8},
     number = {4},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1970_8_4_a4/}
}