@article{DE_2003_39_12_a7,
     author = {M. T. Teryokhin},
     title = {Nonzero {Periodic} {Solutions} of {Nonlinear} {Systems} of {Ordinary} {Differential} {Equations} with a {Singular} {Matrix} {Multiplying} the {Derivatives}},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1645--1653},
     publisher = {mathdoc},
     volume = {39},
     number = {12},
     year = {2003},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_2003_39_12_a7/}
}