@article{SJIM_2022_25_4_a0,
     author = {N. B. Ayupova and V. P. Golubyatnikov and L. S. Minushkina},
     title = {On invariant surfaces in phase portraits
},
     journal = {Sibirskij \v{z}urnal industrialʹnoj matematiki},
     pages = {5--13},
     publisher = {mathdoc},
     volume = {25},
     number = {4},
     year = {2022},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/SJIM_2022_25_4_a0/}
}