Voir la notice de l'article provenant de la source Math-Net.Ru
@article{MZM_1999_65_3_a16, author = {T. Yu. Kulikova}, title = {On the approximation of functions by a~hyperbolic angle in the $L_2$ metric}, journal = {Matemati\v{c}eskie zametki}, pages = {471--474}, publisher = {mathdoc}, volume = {65}, number = {3}, year = {1999}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1999_65_3_a16/} }
T. Yu. Kulikova. On the approximation of functions by a~hyperbolic angle in the $L_2$ metric. Matematičeskie zametki, Tome 65 (1999) no. 3, pp. 471-474. http://geodesic.mathdoc.fr/item/MZM_1999_65_3_a16/