"Taylor Swift's Dating Tips: Glamour's March Cover Star on the One Thing She Won't Do in Relationships". Interview with Cindi Leive, www.glamour.com. February 4, 2014.
Ken Schwaber, Jeff Sutherland (2012). “Software in 30 Days: How Agile Managers Beat the Odds, Delight Their Customers, And Leave Competitors In the Dust”, p.51, John Wiley & Sons
Stephen R. Covey (1994). “Daily Reflections for Highly Effective People: Living THE SEVEN HABITS OF HIGHLY SUCCESSFUL PEOPLE Every Day”, p.201, Simon and Schuster