- This is about TeX but it's a great book. Covers from small things to internals of TeX and typography. Definitely worth reading.
- Mostly intended for beginners but actually more appropriate for heavy LaTeX users. It covers all the basics and then goes on to more advanced subjects like drawing and advanced customizations. Lots of examples, very good explanations.
- A classic in mindfulness meditation. You can read it online here
- The Not So Short Introduction to LaTeX2eMore than enough to get you started. Included in most LaTeX distributions. (Usually available here)
- Another excellent book on programming by MIT press. Available for online reading.
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