@article{TRSPY_1976_140_a13,
     author = {V. R. Portnov},
     title = {S.\,L.~Sobolev projection operators for seminorms with infinite-dimensional kernels},
     journal = {Informatics and Automation},
     pages = {252--263},
     publisher = {mathdoc},
     volume = {140},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TRSPY_1976_140_a13/}
}