B. Klin, P. Hoffman, A. Tarlecki, L. Schröder, и T. Mossakowski. Mathematical Foundations of Computer Science, том 2136 из Lecture Notes in Computer Science, стр. 512--523. Springer; Berlin; http://www.springer.de, (2001)
L. Schröder, T. Mossakowski, P. Hoffman, B. Klin, и A. Tarlecki. Fundamental Approaches to Software Engineering, том 2029 из Lecture Notes in Computer Science, стр. 253--268. Springer; Berlin; http://www.springer.de, (2001)
L. Schröder, T. Mossakowski, и A. Tarlecki. International Colloquium on Automata, Languages and Programming (ICALP 2001), том 2076 из Lecture Notes in Computer Science, стр. 993-1004. Springer; Berlin; http://www.springer.de, (2001)