@article{SF_1988__37_1_134928,
     author = {Karl H. Hofmann and Joachim Hilgert},
     title = {Invariant cones in {Lie} algebras.},
     journal = {Semigroup forum},
     pages = {241--252},
     publisher = {mathdoc},
     volume = {37},
     number = {1},
     year = {1988},
     zbl = {0648.22005},
     url = {http://geodesic.mathdoc.fr/item/SF_1988__37_1_134928/}
}