A Flexagon made with Square faces. Gardner (1961) shows how to construct a tri-tetraflexagon,
tetra-tetraflexagon,
and hexa-tetraflexagon.
See also Flexagon, Flexatube, Hexaflexagon
References
Chapman, P. B. ``Square Flexagons.'' Math. Gaz. 45, 192-194, 1961.
Cundy, H. and Rollett, A. Mathematical Models, 3rd ed. Stradbroke, England: Tarquin Pub., p. 207, 1989.
Gardner, M. Ch. 1 in The Scientific American Book of Mathematical Puzzles & Diversions. New York:
Simon and Schuster, 1959.
Gardner, M. Ch. 2 in The Second Scientific American Book of Mathematical Puzzles & Diversions: A New Selection.
New York: Simon and Schuster, 1961.
Pappas, T. ``Making a Tri-Tetra Flexagon.'' The Joy of Mathematics.
San Carlos, CA: Wide World Publ./Tetra, p. 107, 1989.