@article{PDM_2012_4_a0,
     author = {K. G. Kogos and V. M. Fomichev},
     title = {Positive properties of non-negative matrices},
     journal = {Prikladna\^a diskretna\^a matematika},
     pages = {5--13},
     year = {2012},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/PDM_2012_4_a0/}
}