@article{DE_1969_5_3_a16,
     author = {V. M. Lebedeva},
     title = {The number of periodic solutions of a first order equation with rational right hand side},
     journal = {Differencialʹnye uravneni\^a},
     pages = {560--562},
     publisher = {mathdoc},
     volume = {5},
     number = {3},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1969_5_3_a16/}
}