@article{KYB_1971_7_1_a0,
     author = {Mandl, Petr},
     title = {On the variance in controlled {Markov} chains},
     journal = {Kybernetika},
     pages = {1--12},
     year = {1971},
     volume = {7},
     number = {1},
     mrnumber = {0286178},
     zbl = {0215.25902},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/KYB_1971_7_1_a0/}
}