The following publications are possibly variants of this publication:
- Addendum to On Satisfiability, Equivalence, and Implication Problems Involving Conjunctive Queries in Database Systems Sha Guo, Wei Sun, Mark Allen Weiss. tkde, 10(5):863, 1998. [doi]
- Solving Implication Problems in Database ApplicationsXian-He Sun, Nabil Kamel, Lionel M. Ni. SIGMOD 1989: 185-192 [doi]
- On Satisfiability, Equivalence, and Impication Problems Involving Conjunctive Queries in Database SystemsSha Guo, Wei Sun, Mark Allen Weiss. tkde, 8(4):604-616, 1996. [doi]