@article{DAN_1994_335_1_a10,
     author = {A. S. Venetskii and V. A. Kaloshin},
     title = {The design of an axially symmetric gradient lens when one of the},
     journal = {Doklady Akademii Nauk},
     pages = {39--41},
     publisher = {mathdoc},
     volume = {335},
     number = {1},
     year = {1994},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1994_335_1_a10/}
}