@article{DAN_1971_197_4_a13,
     author = {Geza Froid},
     title = {On an inequality of {Markov} type},
     journal = {Doklady Akademii Nauk},
     pages = {790--793},
     year = {1971},
     volume = {197},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1971_197_4_a13/}
}