APA (7th ed.) Citation

Reader's Digest Association. (2005). Word power builder: Improve your English as you build your vocabulary. Reader's Digest Association.

Chicago Style (17th ed.) Citation

Reader's Digest Association. Word Power Builder: Improve Your English as You Build Your Vocabulary. New York: Reader's Digest Association, 2005.

MLA (8th ed.) Citation

Reader's Digest Association. Word Power Builder: Improve Your English as You Build Your Vocabulary. Reader's Digest Association, 2005.