1. R. Backofen and G. Smolka. A complete and recursive feature theory. Research Report RR-92-30, DFKI, Saarbrücken, Sept. 1992. To appear in Theoretical Computer Science.
2. R. Backofen and R. Treinen. How to win a game with features. In J.-P. Jouannaud, editor, Proc. Int. Conf. on Constraints in Computational Logics, volume 845 of Lecture Notes in Computer Science, pages 320–335. Springer-Verlag, Sept. 1994.
3. A. Boudet. Combining unification algorithms. Journal of Symbolic Computation, 16:597–626, 1993.
4. A.-C. Caron, J.-L. Coquidé, and M. Dauchet. Encompassment properties and automata with constraints. In C. Kirchner, editor, Proc. 5th. Int. Conf. on Rewriting Techniques and Applications, Lecture Notes in Computer Science, vol. 690, Montreal, Canada, 1993. Springer-Verlag.
5. H. Comon. Disunification: a survey. In J.-L. Lassez and G. Plotkin, editors, Computational Logic: Essays in Honor of Alan Robinson. MIT Press, 1991.