@article{DAN_1990_315_4_a9,
     author = {Yu. M. Davydov},
     title = {Formation of a zone with increased concentration of particles under focused
},
     journal = {Doklady Akademii Nauk},
     pages = {813--815},
     publisher = {mathdoc},
     volume = {315},
     number = {4},
     year = {1990},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1990_315_4_a9/}
}