@article{DAN_1967_175_3_a5,
     author = {N. M. Mitrofanova},
     title = {Non-trivial sufficient statistics for observations connected in a {Markov} chain},
     journal = {Doklady Akademii Nauk},
     pages = {528--531},
     publisher = {mathdoc},
     volume = {175},
     number = {3},
     year = {1967},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1967_175_3_a5/}
}