@article{10_21136_CMJ_1975_101301,
     author = {Mi\v{s}{\'\i}k, Ladislav},
     title = {\"Uber approximative derivierte {Zahlen}},
     journal = {Czechoslovak Mathematical Journal},
     pages = {154--159},
     publisher = {mathdoc},
     volume = {25},
     number = {1},
     year = {1975},
     doi = {10.21136/CMJ.1975.101301},
     mrnumber = {0369634},
     zbl = {0308.26004},
     language = {ge},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1975.101301/}
}