@article{JRAM_1971__251_151153,
     author = {Otton Martin Nikodym},
     title = {A study in the {Lagranges} variational problem considered in the large.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {20--31},
     publisher = {mathdoc},
     volume = {251},
     year = {1971},
     zbl = {0252.49011},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1971__251_151153/}
}