Richard Cook's writing and talks on systems have hugely shaped my thinking on systems.

For those interested in more, he gave a highly entertaining talk on system resiliency here and introduces a helpful model. https://www.youtube.com/watch?v=PGLYEDpNu60

I also wrote a post summarizing how I think about Rasmussen’s model in startups and web applications. https://medium.com/@sunils34/managing-systems-ecbf161066cf