- «The Art of Friendship:A Guide to Understanding and Managing Friendships» (2003)
- «The Friendship Book:Insights and Inspiration on Friendship from World Cultures and Traditions» (2006)
- «The Friendship Journal:A Guided Journey to Discover and Nurture Your Friendships» (2008)
- «The Joy of Friendship:Celebrating Every Occasion and Strengthening Your Relationships» (2010)
- «Η δύναμη της φιλίας:Πώς να ανακαλύψετε, να εμπλουτίσετε και να θρέψετε τις πιο πολύτιμες σχέσεις σας» (2012)