@article{JSFU_2009_2_3_a6,
     author = {Vladislav S. Krotkin and Oleg V. Kuzmin},
     title = {Cardinality of the {Ryser} {Classes} and the {Motzkin} {Paths} with {Weights}},
     journal = {\v{Z}urnal Sibirskogo federalʹnogo universiteta. Matematika i fizika},
     pages = {312--318},
     publisher = {mathdoc},
     volume = {2},
     number = {3},
     year = {2009},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/JSFU_2009_2_3_a6/}
}