He then became a research assistant at the University of Tübingen and in 1971/72 an assistant professor at Carleton University (where he collaborated with Vlastimil Dlab).
Danach war er wissenschaftlicher Assistent an der Universität Tübingen und 1971/72 Assistenzprofessor an der Carleton University (wo er mit Vlastimil Dlab zusammenarbeitete).