APA (7th ed.) Citation

Powell, B., & Lawlor, P. (2018). Relentless forward progress: A guide to running ultramarathons (Unabridged.). Tantor Media.

Chicago Style (17th ed.) Citation

Powell, Bryon, and Patrick Lawlor. Relentless Forward Progress: A Guide to Running Ultramarathons. Unabridged. Old Saybrook: Tantor Media, 2018.

MLA (8th ed.) Citation

Powell, Bryon, and Patrick Lawlor. Relentless Forward Progress: A Guide to Running Ultramarathons. Unabridged. Tantor Media, 2018.

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