@article{IVM_2009_8_a9, author = {M. T. Teryokhin}, title = {The limit cycles of a~second-order system of differential equations: the method of small forms}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {73--82}, publisher = {mathdoc}, number = {8}, year = {2009}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_2009_8_a9/} }