@article{MZ_1937__42_168704,
     author = {F., Klein-Barmen},
     title = {Birkhoffsche und harmonische {Verb\"ande}},
     journal = {Mathematische Zeitschrift},
     pages = {58--81},
     publisher = {mathdoc},
     volume = {42},
     year = {1937},
     zbl = {0015.29105},
     url = {http://geodesic.mathdoc.fr/item/MZ_1937__42_168704/}
}