@article{JLT_1999_9_1_a6,
     author = {D. Burde},
     title = {Degenerations of {Nilpotent} {Lie} {Algebras}},
     journal = {Journal of Lie theory},
     pages = {193--202},
     year = {1999},
     volume = {9},
     number = {1},
     url = {http://geodesic.mathdoc.fr/item/JLT_1999_9_1_a6/}
}