The best thing would be to get the actual data from the process of writing the book. E.g. if the book had been written using Git, we would have the commits.
I’m assuming it wasn’t written in Git, so we’ll need to create manual nodes to represent the creation process. With the manual plugin, we can still do a pretty good job with specific cred attribution.
If it were written in a text editor with distinct drafts, and the drafts went out to individuals for feedback, then we could make a node for each draft, and connect each draft to its reviewers. Each draft would also flow cred to the previous draft. Then we could also publish the drafts, and future cred-historians can tweak the weights on the individual drafts depending on how much new value each draft added.
However, the manual plugin doesn’t exist yet . So for now you could consider having adamhjk make an issue in the repo which is like “placeholder for thanking the SFOSC book reviewers” and contains references to them. Then you could put a really big weight on that initial commit (to flow cred to adamhjk) and a big weight on the reviewers (to flow cred to the reviewers). Later we would remove those weights once we had the manual plugin up and running.