1. Apt, K. R., Blair, H. A., & Walker, A. (1987). Towards a theory of declarative knowledge. In J. Minker (Ed.), Foundations of deductive databases and logic programming [Min87] (pp. 89–148). Los Altos: Morgan Kaufmann.
This influential paper identifies the notion of stratification as an effective approach to embedding negation in logic programming, both computationally and cognitively. It develops its general theory and fixpoint semantics, and specializes SLD-resolution to it.
2. Andreoli, J. -M. (1992). Logic programming with focusing proofs in linear logic. Journal of Logic and Computation, 2(3), 297–347.
This paper is the first systematic investigation of focusing, a proof technique that underlies much of the recent research in logic programming. Focusing relies on the observation that, when in a proof, some steps can be permuted without affecting the ability to complete the proof. Focusing systematically delays some steps while eagerly carrying out others, which results in a very efficient strategy.
3. Ceri, S., Gottlob, G., & Tanca, L. (1990). Logic programming and databases. Berlin/New York: Springer.
This expanded version of [CGT89] is an excellent survey with some in-depth analysis of important concepts, in particular semantics, optimizations and the interface with actual databases. It covers the experimental deductive database system of the time at length.
4. Chandra, A. K., & Harel, D. (1985). Horn clause queries and generalizations. Journal of Logic Programming, 1, 1–15.
This paper provides a detailed classification of the expressive powers of various fragments of relational algebra and (extensions of) Datalog. It is particularly concerned with how different forms of negation impact expressiveness.
5. Chaudhuri, K. (2006). The focused inverse method for linear logic. PhD thesis, Computer Science Department, Carnegie Mellon University.
This dissertation combines two established approaches to automate reasoning more effectively in a refinement of traditional logic called linear logic. These are the inverse method, due to Maslov, and Andreoli’s focusing [And92].