  This paper explores the problem of determining which classes of Petri nets
can be encoded into behaviourally-equivalent CCS processes. Most of the
existing related literature focuses on the inverse problem (i.e., encoding
process calculi belonging to the CCS family into Petri nets), or extends CCS
with Petri net-like multi-synchronisation (Multi-CCS). In this work, our main
focus are free-choice and workflow nets (which are widely used in process
mining to describe system interactions) and our target is plain CCS. We present
several novel encodings, including one from free-choice workflow nets (produced
by process mining algorithms like the alpha-miner) into CCS processes, and we
prove that our encodings produce CCS processes that are weakly bisimilar to the
original net. Besides contributing new expressiveness results, our encodings
open a door towards bringing analysis and verification techniques from the
realm of process calculi into the realm of process mining.
