@article{JRAM_1970__244_151045,
     author = {Nickolas Heerema},
     title = {A group of a {Lie} algebra.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {112--118},
     year = {1970},
     volume = {244},
     zbl = {0205.05303},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1970__244_151045/}
}