@article{KYB_1979__15_2_a2,
     author = {\v{Z}\'ak, Stanislav},
     title = {A {Turing} machine space hierarchy},
     journal = {Kybernetika},
     pages = {--121},
     publisher = {mathdoc},
     volume = {15},
     number = {2},
     year = {1979},
     mrnumber = {542056},
     zbl = {0421.68050},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/KYB_1979__15_2_a2/}
}