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.
J. W. M. Stroet, R. Engmann. Manipulation of expression in a relational algebra. Inf. Syst., 4(1):195-203, 1979.
Abstract is missing.