Doctor of Philosophy, Habilitation University Basel, Switzerland, 1961, 1965.
Professor of Economics, University Heidelberg, 1965-1972. Visiting Professor, Massachusetts Institute of Technology, Cambridge, Mass., USA, 1968-1970. Professor of Economics, University Bielefeld, 1972-1974, University Bonn, 1974-1982.
Professor of Economics, University Berne, Switzerland, since 1982.
Theory of optimal growth: ‘golden rule’ and ‘overtaking criterion’. Theory of technical progress: theory of induced technical change. Capital theory: duality relations in capital theory.
Steady state capital theory. Coefficient of intertemporal substitution. Welfare economics of endogenous tastes.
Concept of barriers to entry. Proposals for reform of the telecommunications sector.