Petri nets and algebraic calculi of processes, with G. Roucairol and R. De Simone, in Advances in Petri Nets, Lecture Notes in Computer Science (LNCS) Vol 222 (1985), 41-58.

We show that, as transition systems, Petri nets may be expressed by terms of a calculus of processes which is a variant of Milner's SCCS. We then prove that the class of labelled nets form a subcalculus, thus an algebra, with juxtaposition, adding condition and labelling as primitive operations. Finally we introduce rational machines which express explicit synchronizations on nets.