@article{DAN_1957_116_4_a4,
     author = {A. I. Koshelev},
     title = {On the boundedness in $L_p$ of derived solutions of elliptical equations and elliptical systems},
     journal = {Doklady Akademii Nauk},
     pages = {542--544},
     publisher = {mathdoc},
     volume = {116},
     number = {4},
     year = {1957},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1957_116_4_a4/}
}