Theodore Roosevelt (2015). “Theodore Roosevelt on Bravery: Lessons from the Most Courageous Leader of the Twentieth Century”, p.4, Skyhorse Publishing, Inc.
"Smarter Branding Without Breaking the Bank: Five Proven Marketing Strategies You Can Use Right Now to Build Your Business at Little Or No Cost". Book by Brenda Bence (p. 91), November 7, 2011.