Voir la notice de l'article provenant de la source Math-Net.Ru
@article{MZM_1986_39_1_a1, author = {V. G. Sheretov}, title = {Tests for extremality in a problem for quasiconformal mappings}, journal = {Matemati\v{c}eskie zametki}, pages = {14--23}, publisher = {mathdoc}, volume = {39}, number = {1}, year = {1986}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1986_39_1_a1/} }
V. G. Sheretov. Tests for extremality in a problem for quasiconformal mappings. Matematičeskie zametki, Tome 39 (1986) no. 1, pp. 14-23. http://geodesic.mathdoc.fr/item/MZM_1986_39_1_a1/