@article{DAN_1972_206_4_a4,
     author = {N. B. Engibaryan and M. A. Mnatsakanyan},
     title = {On the factorization of integral operators},
     journal = {Doklady Akademii Nauk},
     pages = {792--795},
     publisher = {mathdoc},
     volume = {206},
     number = {4},
     year = {1972},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1972_206_4_a4/}
}