@article{DAN_1986_286_5_a0,
     author = {K. Alymkulov},
     title = {Periodic solutions of a system that is obtained by singular},
     journal = {Doklady Akademii Nauk},
     pages = {1033--1037},
     publisher = {mathdoc},
     volume = {286},
     number = {5},
     year = {1986},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1986_286_5_a0/}
}