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Naval is giving his great book for free on his website for a long time. You can get the book by the link below https://www.navalmanack.com/
Record main lessons and stories used to explain those lessons in an easy to retrieve format. You can make a docx file like this. You can print this if you want handwritten notes I have used it for long. Makes an archive of great book lessons. It can be used to revise great nonfiction books.
little smelly ideas 