%S Lecture Notes in Computer Science %A Rocco De Nicola %E Michal Chytil %E Vaclav Koubek %L eprints392 %D 1984 %B Mathematical Foundations of Computer Science (MFCS 1984) %R 10.1007/BFb0030326 %T Models and Operators for Nondeterministic Processes %P 433-442 %I Springer %V 176