Here is one reference that is more advanced, but I include it for reference, as it's in my clipboard now:

* John C. Baez and Jacob Biamonte, [Quantum techniques for stochastic mechanics](, arXiv:1209.3632 [quant-ph]. Text includes treatment from the ground up of Petri nets, both stochastic and deterministic. Example includes SI, SIR and SIRS models.