@article{SEMR_2008_5_a34,
     author = {E. P. Volokitin and S. A. Treskov},
     title = {About periodic solutions of predator-prey system},
     journal = {Sibirskie \`elektronnye matemati\v{c}eskie izvesti\^a},
     pages = {251--254},
     publisher = {mathdoc},
     volume = {5},
     year = {2008},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/SEMR_2008_5_a34/}
}