If you can read German, somebody also wrote a whole dissertation on the subject of the CD's development history:
https://publications.rwth-aachen.de/record/95066
One of the cool/obscure things is that the center hole exactly matches a then available coin because it made the development and testing easier.
alt Hacker News
One of the cool/obscure things is that the center hole exactly matches a then available coin because it made the development and testing easier.