Jack Canfield, D. D. Watkins (2007). “Jack Canfield's Key to Living the Law of Attraction: A Simple Guide to Creating the Life of Your Dreams”, p.39, Health Communications, Inc.
Jack Canfield, Mark Victor Hansen (2012). “Chicken Soup for the Soul in the Classroom Middle School Edition: Grades 6–8: Lesson Plans and Students' Favorite Stories for Reading Comprehension, Writing Skills, Critical Thinking, Character Building”, p.433, Simon and Schuster