, "Four Major Problem Areas in Programmed Instruction for Modern Language Learning", in : Theodore H. Mueller (ed.)Proceedings of the Seminar on Programmed Learning, New York 1968, 18-37.
, "Le conditionnement sans maître par les exercices structuraux ou la machine à enseigner", in Pierre Delattre (ed.)Les exercices structuraux pour quoi faire?, Paris 1971, 113-124.
, "From Skill Acquisition to Language Control", in : Robert C. Lugton and Charles H. Heinle (eds.)Toward a Cognitive Approach to Second-Language Acquisition, (Language and the Teacher : A series in Applied Linguistics Vol. 17), Philadelphia 1971, 153-168.