Bernhard K. Aichernig, Harald Brandl, Willibald Krenn. Qualitative Action Systems. In Karin Breitman, Ana Cavalcanti, editors, Formal Methods and Software Engineering, 11th International Conference on Formal Engineering Methods, ICFEM 2009, Rio de Janeiro, Brazil, December 9-12, 2009. Proceedings. Volume 5885 of Lecture Notes in Computer Science, pages 206-225, Springer, 2009.