@article{TIMM_2013_19_3_a14,
     author = {L. S. Kazarin},
     title = {On {Ditsman's} lemma},
     journal = {Trudy Instituta matematiki i mehaniki},
     pages = {150--157},
     year = {2013},
     volume = {19},
     number = {3},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TIMM_2013_19_3_a14/}
}