@article{DAN_1968_179_5_a8,
     author = {S. L. Krushkal'},
     title = {A certain class of extremal quasiconformal mappings},
     journal = {Doklady Akademii Nauk},
     pages = {1042--1045},
     publisher = {mathdoc},
     volume = {179},
     number = {5},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1968_179_5_a8/}
}