@article{DAN_1993_328_6_a0,
     author = {I. M. Gel'fand and M. I. Graev},
     title = {$GG$-functions},
     journal = {Doklady Akademii Nauk},
     pages = {645--648},
     publisher = {mathdoc},
     volume = {328},
     number = {6},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1993_328_6_a0/}
}