@article{DAN_1970_193_2_a7,
     author = {V. S. Klimov},
     title = {Second solutions of boundary value problems},
     journal = {Doklady Akademii Nauk},
     pages = {280--283},
     publisher = {mathdoc},
     volume = {193},
     number = {2},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1970_193_2_a7/}
}