Voir la notice de l'article provenant de la source Math-Net.Ru
@misc{KVANT_2018_1_a9, title = {{\CYRZ}{\cyra}{\cyrd}{\cyra}{\cyrch}{\cyri} 17--20}, journal = {Kvant}, pages = {30}, publisher = {mathdoc}, number = {1}, year = {2018}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/KVANT_2018_1_a9/} }
Задачи 17--20. Kvant, no. 1 (2018). http://geodesic.mathdoc.fr/item/KVANT_2018_1_a9/