@article{DE_1982_18_5_a9, author = {I. P. Martynov}, title = {Third-order systems without fixed critical points}, journal = {Differencialʹnye uravneni\^a}, pages = {792--804}, publisher = {mathdoc}, volume = {18}, number = {5}, year = {1982}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1982_18_5_a9/} }