APA
Harden T., Arnd Witte & Dirk Kohler. (2006). The Concept of Progression in the Teaching and Learning of Foreign Languages. Bern: Peter Lang.
Chicago
Harden Theo, Arnd Witte and Dirk Kohler. 2006. The Concept of Progression in the Teaching and Learning of Foreign Languages. Bern: Peter Lang.
Harvard
Harden T., Arnd Witte and Dirk Kohler. (2006). The Concept of Progression in the Teaching and Learning of Foreign Languages. Bern: Peter Lang.
MLA
Harden Theo, Arnd Witte and Dirk Kohler. The Concept of Progression in the Teaching and Learning of Foreign Languages. Bern: Peter Lang. 2006.