@article{DM_1993_5_2_a12,
     author = {V. N. Sachkov and I. B. Oshkin},
     title = {Exponents of classes of non-negative matrices},
     journal = {Diskretnaya Matematika},
     pages = {150--159},
     publisher = {mathdoc},
     volume = {5},
     number = {2},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DM_1993_5_2_a12/}
}