English Beginner Invisible Influence: The Power to Persuade Anyone, Anytime, Anywhere Kevin Hogan 2013 View book
English Advanced The Science of Influence: How to Get Anyone to Say "Yes" in 8 Minutes or Less! Kevin Hogan 2004 View book
English Advanced The Science of Influence: How to Get Anyone to Say 'Yes' in 8 Minutes or Less! Second Edition Kevin Hogan 2010 View book