@article{TDM_2006_9_a11,
     author = {S. V. Polin},
     title = {An application of topos theory to the investigation of cryptosystems},
     journal = {Trudy po diskretnoj matematike},
     pages = {220--252},
     publisher = {mathdoc},
     volume = {9},
     year = {2006},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TDM_2006_9_a11/}
}