@article{SVFU_2022_29_2_a5,
     author = {R. Boukoucha},
     title = {Limit cycles and phase portrait for a class of differential systems},
     journal = {Matemati\v{c}eskie zametki SVFU},
     pages = {72--81},
     year = {2022},
     volume = {29},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/SVFU_2022_29_2_a5/}
}