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2. M. Ben-Ari. Mathematical Logic for Computer Science. Prentice Hall, 1993.
3. E. Best. Representing a program invariant as a linear invariant in a Petri net. EATCS Bulletin, (17): 2–11, June 1982.
4. E. Best. Semantik. Vieweg-Verlag, 1995.
5. E. Best and C. Fernández. Nonsequential Processes, volume 13 of EATCS Monographs on Theoretical Computer Science. Springer-Verlag, 1988.