@article{DAN_1957_117_6_a11,
     author = {N. A. Potapkov},
     title = {On the anisotropy of cubic crystals},
     journal = {Doklady Akademii Nauk},
     pages = {965--966},
     publisher = {mathdoc},
     volume = {117},
     number = {6},
     year = {1957},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1957_117_6_a11/}
}