@article{IVM_1996_11_a7,
     author = {V. V. Petrova and E. L. Tonkov},
     title = {Admissibility of periodic processes and existence theorems for periodic {solutions.~I}},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {65--72},
     publisher = {mathdoc},
     number = {11},
     year = {1996},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1996_11_a7/}
}