@article{702294,
title = {Faktorizatsiia i neponizhenie ostsilliatsii na okruzhnosti},
booktitle = {Equadiff 5},
series = {GDML\_Books},
publisher = {BSB B.G. Teubner Verlagsgesellschaft},
address = {Leipzig},
year = {1982},
pages = {226-227},
zbl = {0548.34036},
url = {http://dml.mathdoc.fr/item/702294}
}
Levin, Anatoliĭ. Факторизация и непонижение осцилляции на окружности, dans Equadiff 5, GDML_Books, (1982), pp. 226-227. http://gdmltest.u-ga.fr/item/702294/