Doctor of Philosophy, University Marburg, Germany, 1956. Habilitation, University Marburg, 1964.
Lecturer in Indian and Tibetan philology University Marburg, 1964-1969, professor, 1969-1976. Professor Indology University Bonn, Federal Republic Germany, 1976-1998, emeritus professor, 1998. Honorary professor Tibetology, University Göttingen, Federal Republic Germany, since 1989.
Fellow Royal Asiatic Society. Member German Oriental Society, Rheno-Westphalian Academy Letters and Sciences.