Researchr is a web site for finding, collecting, sharing, and reviewing scientific publications, for researchers by researchers.
Sign up for an account to create a profile with publication list, tag and review your related work, and share bibliographies with your co-authors.
Yechezkel Zalcstein. Group-Complexity and Reversals of Finite Semigroups. Theory Comput. Syst., 8(3):235-242, 1975.