@article{MAN_1989__284_4_164548,
     author = {Wolfgang Soergel},
     title = {Universelle versus relative {Einh\"ullende:} {Eine} geometrische {Untersuchung} von {Quotienten} von universellen {Einh\"ullenden} halbeinfacher {Lie-Algebren.}},
     journal = {Mathematische Annalen},
     pages = {177--198},
     publisher = {mathdoc},
     volume = {284},
     number = {4},
     year = {1989},
     zbl = {0649.17012},
     url = {http://geodesic.mathdoc.fr/item/MAN_1989__284_4_164548/}
}