the 3-3 duopyramid, while the 6 edges connecting the two triangles are not included. It can be seen in a hexagonal projection with 3 sets of colored edges. This arrangement of vertices and edges makes a complete bipartite graph with each vertex from one triangle is connected to every vertex on the other. It is also called a Thomsen graph or 4-cage. See also 3-4 duoprism Tesseract (4-4 duoprism) 5-5 duoprism Convex regular 4-polytope Duocylinder Notes References Regular Polytopes, H. S. M. Coxeter, Dover Publications, Inc., 1973, New York, p. 124. Coxeter, The Beauty of Geometry: Twelve Essays, Dover Publications, 1999, (Chapter 5: Regular Skew Polyhedra in three and four dimensions and their topological analogues) Coxeter, H. S. M. Regular Skew Polyhedra in Three and Four Dimensions. Proc. London Math. Soc. 43, 33-62, 1937. John H. Conway, Heidi Burgiel, Chaim Goodman-Strass, The Symmetries of Things 2008, (Chapter 26) Norman Johnson Uniform Polytopes, Manuscript (1991) N.W. Johnson: The Theory of Uniform Polytopes and Honeycombs, Ph.D. Dissertation, University of Toronto, 1966 Apollonian Ball Packings and Stacked Polytopes Discrete & Computational Geometry, June 2016, Volume 55, Issue 4, pp 801–826 External links The Fourth Dimension Simply Explained—describes duoprisms as "double prisms" and duocylinders as "double cylinders" Polygloss – glossary of higher-dimensional terms Exploring Hyperspace with the Geometric Product 4-polytopes