Bastian G. Kruidenier

Second-Language Acquisition through Subject-Matter Learning: A Study of Sheltered Psychology Classes at the University of Ottawa.

H. P. Edwards, Stephen Krashen, Marjorie Bingham Wesche, 1984 .

Aptitude, Attitude and Motivation in Second Language Proficiency: A Test Of Clément's Model

R. Clément, B. Kruidenier, Richard Clément, 1985 .