On the lengths of pairs of complex matrices of size at most five. (English)
Bull. Aust. Math. Soc. 73, No. 3, 461-472 (2006).
1
Subalgebras of incidence algebras determined by equivalence relations (English)
J. Comb. Theory, Ser. A 31, No. 1, 94-97 (1981).
2