@article{DE_2006_42_5_a10,
     author = {A. N. Karapetyants and V. A. Nogin},
     title = {Estimates for twisted convolution operators with singularities of kernels on a sphere and at the origin},
     journal = {Differencialʹnye uravneni\^a},
     pages = {674--683},
     publisher = {mathdoc},
     volume = {42},
     number = {5},
     year = {2006},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_2006_42_5_a10/}
}