@article{DAN_1987_295_1_a1,
     author = {I. M. Gel'fand and M. I. Graev and A. V. Zelevinskii},
     title = {Holonomic systems of equations and series of hypergeometric type},
     journal = {Doklady Akademii Nauk},
     pages = {14--19},
     publisher = {mathdoc},
     volume = {295},
     number = {1},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1987_295_1_a1/}
}