The Cartesian graph product , also called the graph box product and sometimes
simply known as "the" graph product (Beineke and Wilson 2004, p. 104)
and sometimes denoted (e.g., Salazar and Ugalde 2004; though this notation
is more commonly used for the distinct graph tensor
product) of graphs and with disjoint point sets and and edge sets and is the graph with point set and adjacent with whenever or (Harary 1994, p. 22).

If
is a unit-distance graph, then so is .
More generally, a simple relationship exists between the graph
dimension of and that of (Erdős et al. 1965, Buckley and Harary
1988).

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