@article{DAN_1979_249_6_a4,
     author = {M. M. Lavrent'ev and K. G. Reznitskaya},
     title = {An inverse problem with unknown source},
     journal = {Doklady Akademii Nauk},
     pages = {1302--1304},
     year = {1979},
     volume = {249},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1979_249_6_a4/}
}