Duparc, Jacques,
Finkel, Olivier and
Ressayre, Jean-Pierre. 2014.
“The Wadge Hierarchy of Petri Nets w-Languages.” in
Logic, Computation, Hierarchies, edited by Vasco
Brattka, Hannes
Diener, and Dieter
Spreen, pp. 109–138.
Ontos Mathematical Logic n. 4. Berlin: de Gruyter.