Three related types of puzzles are featured in this book. All involve labeling the
vertices or edges of graphs. The first type of graph is a polycube. The vertices are
labeled with a specific set of numbers and the puzzle involves obtaining a labeling in
which the four vertices belonging to each face of a constituent cube have the same
sum. The second type of graph is a plane triangulation. The puzzle involves labeling
the edges of each constituent triangle so that the sum is the same for each triangle.
The third type of graph is a polyhex. For this type of graph the vertices are labeled
with integers so that the sum of the six points bounding each hexagon is the same.
Problems and research questions are included at the end of each Section, and all
puzzle solutions are provided.

Author is a retired Professor of Mathematics still active in the creation and publication of original mathematical works including several mathematical puzzle books. Currently residing on the Oregon coast with wife Sylvie and enjoying a life of meditation on the Inner Light and Sound as a long-time initiate of Sant Thakar Singh.