@article{IM2_1970_4_1_a7,
     author = {J. V. Rybalov},
     title = {On imbedding theorems for a natural extension of the sobolev class $W^l_p(\Omega)$},
     journal = {Izvestiya. Mathematics },
     pages = {147--157},
     publisher = {mathdoc},
     volume = {4},
     number = {1},
     year = {1970},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1970_4_1_a7/}
}