* How to Solve it by Polya https://www.amazon.com/How-Solve-Mathematical-Princeton-Scie... and How to Prove it by Velleman https://www.amazon.com/How-Prove-Structured-Approach-2nd/dp/... helped strengthen that understanding.
* This year I am trying to master https://www.amazon.com/Methods-Mathematics-Calculus-Probabil... which focuses on how to "connect the dots".
* I am using Geometry and the Imagination by Hilbert https://www.amazon.com/Geometry-Imagination-AMS-Chelsea-Publ... as an attempt to "immerse" myself in Geometry. I just love this book.
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