@article{JDM_1934__43_145982,
     author = {Alfred Lotze},
     title = {Zur vektoriellen {Begr\"undung} der sph\"arischen {Trigonometrie.}},
     journal = {Jahresbericht der Deutschen Mathematiker-Vereinigung},
     pages = {81--86},
     publisher = {mathdoc},
     volume = {43},
     year = {1934},
     zbl = {0007.22303},
     url = {http://geodesic.mathdoc.fr/item/JDM_1934__43_145982/}
}