APA (7th ed.) Citation

Berkley, S. (2009). Speak to influence: How to unlock the hidden power of your voice. Ar-Risalah Product.

Chicago Style (17th ed.) Citation

Berkley, Susan. Speak to Influence: How to Unlock the Hidden Power of Your Voice. Kuala Lumpur, Malaysia: Ar-Risalah Product, 2009.

MLA (9th ed.) Citation

Berkley, Susan. Speak to Influence: How to Unlock the Hidden Power of Your Voice. Ar-Risalah Product, 2009.