@article{DAN_1977_235_5_a7,
     author = {S. M. Ponomarev},
     title = {On an eigenvalue problem for the {Lavrent'ev{\textendash}Bicadze} equation},
     journal = {Doklady Akademii Nauk},
     pages = {1020--1021},
     year = {1977},
     volume = {235},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1977_235_5_a7/}
}