@article{IVM_1993_5_a4,
     author = {S. A. Gusarenko},
     title = {A criterion for the reducibility of operator equations},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {43--45},
     publisher = {mathdoc},
     number = {5},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1993_5_a4/}
}