* {{cite book | last=Kiefer | first=Klaus H. | title=Carl-Einstein-Kolloquium, 1994 | publisher=Peter Lang Gmbh, Internationaler Verlag Der Wissenschaften | publication-place=Frankfurt am Main ; New York | date=1996 | isbn=3-631-47991-3 | language=de}}
<ref name="p908">{{cite book | last=Kiefer | first=Klaus H. | title=Carl-Einstein-Kolloquium, 1994 | publisher=Peter Lang Gmbh, Internationaler Verlag Der Wissenschaften | publication-place=Frankfurt am Main ; New York | date=1996 | isbn=3-631-47991-3 | language=de | page=}}</ref>