@article{ZNSL_1981_113_a18,
     author = {P. A. Shvartsman},
     title = {Extension theorems with preservation of local approximation properties of functions in the nonisotropic case},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {247--252},
     publisher = {mathdoc},
     volume = {113},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1981_113_a18/}
}