Found 2 comments on HN
DanBC · 2017-07-08 · Original thread
You need to rethink.

Many doctors will tell you how useful some colouring-in books were to them.

Here's one example, but there are others:

Richard Feynman said that if you wanted to quickly learn a subject you'd start with the books for children to get a quick overview.

DanBC · 2017-03-03 · Original thread
It's a long running tradition, especially in medical education.

Here's an edition from 17 years ago:

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