@article{DAN_1996_346_5_a15,
     author = {M. L. Gerver and E. A. Kudryavtseva},
     title = {On the boundary set of solutions in travel time inversion},
     journal = {Doklady Akademii Nauk},
     pages = {672--674},
     year = {1996},
     volume = {346},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1996_346_5_a15/}
}