, 1968, Meaning as multiple reference, in , Plenarsitzungen, Freiburg-Basel-Wien, Herder, pp. 340-345.
with Moravcsik, J. , Suppes, P. (eds) , 1974, Approaches to natural language, Reidel, Dordrecht.
, 1975a, 'Die Intentionen der Intentionalität', Neue Hefte für Philosophie 8, 65-95.
, 1975b, The intentions of intentionality and other new models for modalities, Reidel, Dordrecht.
, 1976a, Reply to J. N. Findlay, in J. Manninen & R. Tuomela (eds.), Essays on explanation and understanding, Dordrecht, Springer, pp. 117-119.