@article{INTO_2021_194_a15,
     author = {Z. I. Sharifzoda and \`E. M. Muhamadiev and I. D. Nurov},
     title = {Cyclic solutions of the {Pontryagin} equation with a small parameter},
     journal = {Itogi nauki i tehniki. Sovremenna\^a matematika i e\"e prilo\v{z}eni\^a. Temati\v{c}eskie obzory},
     pages = {167--171},
     publisher = {mathdoc},
     volume = {194},
     year = {2021},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/INTO_2021_194_a15/}
}