@article{JRAM_1969__237_150952,
     author = {Walter Klotz},
     title = {Extremalbasen mit fester {Elementeanzahl.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {194--220},
     publisher = {mathdoc},
     volume = {237},
     year = {1969},
     zbl = {0176.32702},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1969__237_150952/}
}