@article{CMH_1930__2_138527,
     author = {F. Gonseth},
     title = {Sur la g\'eom\'etrie des imaginaires {II.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {1--7},
     publisher = {mathdoc},
     volume = {2},
     year = {1930},
     zbl = {56.1160.02},
     url = {http://geodesic.mathdoc.fr/item/CMH_1930__2_138527/}
}