@article{CMUC_1971__12_2_a5,
     author = {H\'ajkov\'a, Marie},
     title = {The lattice of bi-numerations of arithmetic. {II.}},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {281--306},
     publisher = {mathdoc},
     volume = {12},
     number = {2},
     year = {1971},
     mrnumber = {0290970},
     zbl = {0232.02025},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1971__12_2_a5/}
}