Relations and Kleene Algebra in Computer Science [electronic resource] : 11th International Conference on Relational Methods in Computer Science, RelMiCS 2009, and 6th International Conference on Applications of Kleene Algebra, AKA 2009, Doha, Qatar, November 1-5, 2009. Proceedings / edited by Rudolf Berghammer, Ali Mohamed Jaoua, Bernhard Möller.