@article{PDM_2009_10_a20,
     author = {M. A. Kachanov},
     title = {Closure of basic role {DP-model}},
     journal = {Prikladna\^a diskretna\^a matematika},
     pages = {41--44},
     publisher = {mathdoc},
     number = {10},
     year = {2009},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/PDM_2009_10_a20/}
}