1"Cataplexy." SleepFoundation.org. Accessed: April 28, 2020.
2Cuevas, Mayra. "Breathe. Laugh. Be happy. The Science Behind Laughter Yoga." CNN: Health, Updated December 4, 2018. Accessed: April 28, 2020.
3Dwyer, Lexi. "When Do Babies Start Laughing?" Today, December 16, 2019. Accessed: April 28, 2020.
4Higuera, Valencia. "Can You Die from Laughing?" Healthline. June 11, 2019. Accessed: April 28, 2020.
5Marano, Hara Estroff. "Laughter: The Best Medicine." Psychology Today, April 5, 2005. Updated: June 9, 2016. Accessed: April 28, 2020.
6Provine, Robert. "A Big Mystery: Why Do We Laugh." NBC News, May 27, 1999. Accessed: April 28, 2020.
7Provine, Robert. Laughter: A Scientific Investigation. Auckland, New Zealand: Penguin Books, 2000.
8Ramachandran, V.S. A Brief Tour of Human Consciousness. New York: Pearson Education, Inc, 2004.
9"Research Proves Couples That Laugh Together Are in It for the Long Haul." Huff Post, February 10, 2017. Accessed: April 28, 2020.
10Specktor, Brandon. "If You Have This Phobia, You Literally Can’t Take a Joke." Reader's Digest. Accessed: April 28, 2020.
11———.If You Laugh at These Dark Jokes, You’re Probably a Genius." Reader's Digest. Accessed: April 28, 2020.