@article{DAN_1969_184_6_a3,
     author = {M. I. Kanovitch and N. V. Petri},
     title = {Certain theorems on the complexity of normal algorithms and computations},
     journal = {Doklady Akademii Nauk},
     pages = {1275--1276},
     year = {1969},
     volume = {184},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1969_184_6_a3/}
}