Reuse of modern agile wheel image

[binkley]

A question:
What are the rights/restrictions on reusing the Modern Agile wheel image?

I work on a project that is mostly reading (README, wiki) with advice on a modern build pipeline, and would like to emphasize the practices in Modern Agile:
https://github.com/binkley/modern-java-practices

The project is "Public Domain", and I'd like to eventually publish an open source book based on this, but I want to respect copyrights and give credit.