Found in 2 comments on Hacker News
egypturnash · 2018-12-27 · Original thread
Survival Kit is an advanced book that dives into the deep end, The Illusion Of Life by Frank Thomas and Ollie Johnson [1] (two of the guys on a bunch of the early Disney features) and Cartoon Animation by Preston Blair [2] (countless MGM shorts) will give you a solid grounding in the basics.

The whole article focuses on expanding a list of principles of animation from Illusion.

1: https://www.amazon.com/Illusion-Life-Disney-Animation/dp/078...

2: https://www.amazon.com/Cartoon-Animation-Collectors-Preston-...

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