"Stachel, Hellmuth"@en . . . . "Hellmuth Stachel (born October 6, 1942 in Graz, Austria) is an Austrian mathematician, a Professor of Geometry at the Technical University of Vienna, who is known due to his contributions to geometry, kinematics and computer-aided design."@en . . "Austrian mathematician" . "1942Z"^^ . . . . "1942-10-06Z"^^ . . . "Hellmuth Stachel"@en .