APA (7th ed.) Citation

Allen, D. B., & Allen. (2004). Formula 2+2: The simple solution for successful coaching. Berrett-Koehler.

Chicago Style (17th ed.) Citation

Allen, Douglas B., and Allen. Formula 2+2: The Simple Solution for Successful Coaching. San Francisco: Berrett-Koehler, 2004.

MLA (8th ed.) Citation

Allen, Douglas B., and Allen. Formula 2+2: The Simple Solution for Successful Coaching. Berrett-Koehler, 2004.