@article{DAN_1995_340_2_a3,
     author = {A. V. Kiselev},
     title = {Extremal properties of solutions of inverse boundary value},
     journal = {Doklady Akademii Nauk},
     pages = {161--163},
     publisher = {mathdoc},
     volume = {340},
     number = {2},
     year = {1995},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1995_340_2_a3/}
}