"book-pflow-xyz/chapters/appendix-d-glossary.md" . . "The execution semantics of Petri nets. When a transition fires, it atomically removes tokens from input places and adds tokens to output places according to arc weights. The new marking is $\\mathbf{m}' = \\mathbf{m} + \\mathbf{C} \\cdot \\mathbf{e}_t$ where $\\mathbf{e}_t$ is the unit vector for transition $t$."@en . . "Firing rule"@en .