If .â€œi is a family of sets, its intersection graph has the sets in Y as vertices and an edge between two sets if and only if they overlap. This paper investigates the concept of boxicity of a graphâ€¦ (More)

Roberts, F-S., T-colorings of graphs: re---* bb,Ic results and open problems, Discrete Mathematics 93 (1991) 229-24s. Suppose G is a graph and T is a set of nonnegative integers. A T-coloring of G isâ€¦ (More)

Role assignments, introduced by Everett and Borgatti [2], who called them role colorings, formalize the idea, arising in the theory of social networks, that individuals of the same social role willâ€¦ (More)

An L(2, 1)-coloring of a graph G is a coloring of Gâ€™s vertices with integers in {0, 1, . . . , k} so that adjacent verticesâ€™ colors differ by at least two and colors of distance-two vertices differ.â€¦ (More)

The span Î»(G) of a graph G is the smallest k for which Gâ€™s vertices can be L(2, 1)-colored, i.e., colored with integers in {0, 1, . . . , k} so that adjacent verticesâ€™ colors differ by at least two,â€¦ (More)