"Beginnings: A New Perspective: Life Is Not about the Beginning Or the Ending. It is about the Present Moment" by Catherine Zeeb, Xlibris Corporation, (p. 94), May 12, 2010.
Abraham Lincoln (2013). “Leadership Lessons of Abraham Lincoln: Apply the Principles of the Sixteenth President to Your Own Work and Life”, p.13, Skyhorse Publishing, Inc.