@article{MOMA_1985__100_178248,
     author = {Karl H. Hofmann and Joachim Hilgert},
     title = {Lorentzian {Cones} in {Real} {Lie} {Algebras.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {183--210},
     publisher = {mathdoc},
     volume = {100},
     year = {1985},
     zbl = {0571.22015},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1985__100_178248/}
}