Convex Polytopes

  title={Convex Polytopes},
  author={Branko Grunbaum and Geoffrey C. Shephard},
Graphs, Graphs and Realizations Before proceeding to the graph version of Euler’s formula, some notation will be introduced. A (finite) abstract graph G consists of two sets, the set of vertices V = V(G) = {1, . . . , v} and the set of edges E = E(G) which consists of two-element subsets of V. If {u, w} is an edge, we write also uw for it and call w a neighbour of u and vice versa. If a vertex is contained in an edge or an edge contains a vertex then the vertex and the edge are incident. If two… 

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