Eccentric sequences and eccentric sets in graphs. - Mehdi Behzad; James E. Simpson (Discret. Math., 1976)

Langford sequences: perfect and hooked. - James E. Simpson (Discret. Math., 1983)

A note on perfect systems of difference sets. - James E. Simpson (Discret. Math., 1987)

A bipartite Erdös-Ko-Rado theorem. - James E. Simpson (Discret. Math., 1993)