, 1978, Prometheus unbound?: a new world in the making, in S. Spicker (ed.), Organism, medicine, and metaphysics, Dordrecht, Springer, pp. 1-10.
, 1970a, Toward a science of political economics, in M. Natanson (ed.), Phenomenology and social reality, Den Haag, Nijhoff, pp. 140-173.