@article{DAN_1978_242_1_a5,
     author = {V. A. Zaitsev},
     title = {On {Huygens} principle for some equations with singularities},
     journal = {Doklady Akademii Nauk},
     pages = {28--31},
     publisher = {mathdoc},
     volume = {242},
     number = {1},
     year = {1978},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1978_242_1_a5/}
}