Anders P. Ravn Hans Rischel Formal Techniques in Real-Time and Fault-Tolerant Systems, 5th International Symposium, FTRTFT'98, Lyngby, Denmark, September 14-18, 1998, Proceedings FTRTFT Lecture Notes in Computer Science 1486 Springer 1998 3-540-65003-2 db/conf/ftrtft/ftrtft1998.html