APA način citiranja (7. izdanje)

Ontario Institute for Studies in Education & Harley, B. (1990). The Development of second language proficiency. Cambridge University Press.

Čikaški stil citiranja (17. izdanje)

Ontario Institute for Studies in Education i Birgit Harley. The Development of Second Language Proficiency. Cambridge ; New York: Cambridge University Press, 1990.

MLA način citiranja (8. izdanje)

Ontario Institute for Studies in Education i Birgit Harley. The Development of Second Language Proficiency. Cambridge University Press, 1990.