@article{KYB_1971_7_6_a4,
     author = {Ullrich, Milan and K\v{r}epela, Josef},
     title = {Ein {Beitrag} zu {Stichprobenpl\"anen} mit mehreren {Merkmalen}},
     journal = {Kybernetika},
     pages = {458--466},
     year = {1971},
     volume = {7},
     number = {6},
     mrnumber = {0317501},
     zbl = {0256.62088},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/KYB_1971_7_6_a4/}
}