@article{SM_1979_35_3_a7,
     author = {V. G. Sheretov},
     title = {On the theory of extremal quasiconformal mappings},
     journal = {Sbornik. Mathematics},
     pages = {437--447},
     year = {1979},
     volume = {35},
     number = {3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1979_35_3_a7/}
}