1. Matt Baker, “The Gilbreath Principle,” www.vanishingincmagic.com/blog/the-gilbreath-principle, October 14, 2020.
2. Colm Mulcahy, Card Colm, The First Norman Invasion, www.maa.org/community/maa-columns/past-columns-card-colm/the-first-norman-invasion, August 2005.
3. Colm Mulcahy, Card Colm, The Second Norman Invasion, www.maa.org/community/maa-columns/past-columns-card-colm/the-second-norman-invasion, August 2006.
4. Mathematical Card Magic
5. Magical Mathematics