@article{DAN_1978_239_3_a2,
     author = {A. B. Venkov},
     title = {On the space of cusp functions for a {Fuchsian} group of the first kind with nontrivial commensurator},
     journal = {Doklady Akademii Nauk},
     pages = {511--514},
     publisher = {mathdoc},
     volume = {239},
     number = {3},
     year = {1978},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1978_239_3_a2/}
}