@article{VMUMM_2000_2_a12,
     author = {E. G. Lanina},
     title = {Best approximations of functions and approximations by {Steklov} functions},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {49--52},
     year = {2000},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_2000_2_a12/}
}