@article{10_4153_CJM_1968_023_3,
     author = {Salomaa, Arto},
     title = {On {Events} {Represented} by {Probabilistic} {Automata} of {Different} {Types}},
     journal = {Canadian journal of mathematics},
     pages = {242--251},
     year = {1968},
     volume = {20},
     number = {1},
     doi = {10.4153/CJM-1968-023-3},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1968-023-3/}
}