References:

* John Baez, [Network theory (Part 1)](https://johncarlosbaez.wordpress.com/2011/03/04/network-theory-part-1/), Azimuth Blog, March 4, 2011. Introduction of the idea of green mathematics.
* John Baez, [Green mathematics](https://forum.azimuthproject.org/discussion/1641/green-mathematics), Azimuth Forum, August 2015. Describes a category-theoretic setting for green math.
* John C. Baez and Brendan Fong, [A Compositional Framework for Passive Linear Networks](https://arxiv.org/abs/1504.05625), arXiv:1504.05625v6 [math.CT], Nov 2018.
* John C. Baez and Jacob Biamonte, [Quantum techniques for stochastic mechanics](https://arxiv.org/abs/1209.3632), 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.