@article{10_4064_fm_58_2_229_240,
     author = {Karl Menger and H. Whitlock},
     title = {Two theorems on the generation of systems of functions},
     journal = {Fundamenta Mathematicae},
     pages = {229--240},
     publisher = {mathdoc},
     volume = {58},
     number = {2},
     year = {1966},
     doi = {10.4064/fm-58-2-229-240},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-58-2-229-240/}
}