APA (7th ed.) Citation

HORN, S. (1991). Concentration!: How to focus for success. Crisp Publications.

Chicago Style (17th ed.) Citation

HORN, Sam. Concentration!: How to Focus for Success. California: Crisp Publications, 1991.

MLA (8th ed.) Citation

HORN, Sam. Concentration!: How to Focus for Success. Crisp Publications, 1991.

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