APA (7th ed.) Citation

Garrison, D. R. (1989). Understanding distance education: A framework for the future. Routledge.

Chicago Style (17th ed.) Citation

Garrison, D. R. Understanding Distance Education: A Framework for the Future. London ; New York: Routledge, 1989.

MLA (8th ed.) Citation

Garrison, D. R. Understanding Distance Education: A Framework for the Future. Routledge, 1989.

Warning: These citations may not always be 100% accurate.