found: Wilhelm Ferdinand Lipper, 1972.
found: Musée des beaux-arts d'Orléans. Le dessin français du XVIe au XVIIIe siècle, 1973:page 6 (Claus Bussmann)
found: Johann Conrad Schlaun, 1995?:title page (Klaus Bussmann)
found: Public matters : debates & documents from the Skulptur Projekte Archives, 2019:page facing title page (Klaus Bussmann, 1941-2019 [dedicatee])
found: German Wikipedia, viewed May 8, 2023(Klaus Bussmann; born June 8, 1941, in Aachen; died April 27, 2019, in Münster; German historian and art historian; obtained his doctorate with a thesis on the German architect Wilhelm Ferdinand Lipper)
found: Deutsche Nationalbibliothek online catalog, viewed May 8, 2023(authorized access point: Bussmann, Klaus; other data in authority record: Prof. Dr.; born 1941 in Aachen; died 2019 in Münster (Westfalen); German art historian and museum curator)
