@article{DAN_1967_176_4_a15,
     author = {\`E. G. Shifrin},
     title = {A condition for the breakdown of the region of continuous supersonic},
     journal = {Doklady Akademii Nauk},
     pages = {797--800},
     year = {1967},
     volume = {176},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1967_176_4_a15/}
}