Common Lisp implementations:
- LispWorks has a prolog implementation: Common Prolog(KnowledgeWorks).
- Allegro Common Lisp has a prolog implementation: Allegro Prolog.
- Peter Norvig's excellent Paradigms of Artificial Intelligence Programming (PAIP) contains a Prolog interpreter/compiler in Common Lisp. Source code is available online: http://norvig.com/paip/README.html
- Paul Graham's On Lisp also contains a Prolog compiler.
- Gambol is a basic Prolog interpreter in Common Lisp.
- Qi is a language extending common lisp with prolog capabilities, as well as optional and extensible static type-checking.
- Hideyuki Nakashima wrote a Prolog interpreter that is available from the CMU AI repository: http://www.cs.cmu.edu/afs/cs/project/ai-repository/ai/lang/prolog/impl/prolog/ppicl/0.html (circa 1988, may be a bit rusty)