Based on comments here, I started through "The Game of Chess" by Tarrasch. In the sections I've looked at, every sentence is a gem. It makes some subsequent works seem derivative.
How cool, his thoughts are available to me. It is funny though to see different legends with very different opinions on the same topic. Tarrasch is not shy about his opinions.
Reminds me of football where each side sees very, very different games even though it's the same game. However, even that is instructive.
Care to share any of these gems with us?
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I don't know about the precise ranks, but my list would definitely include Kotov (Think Like a Grandmaster), Botvinnik (almost all his works, but mainly Achieving the Aim and 100 Selected Games), Kasparov (My Great Predecessors), Silman (Endgame Manual), Dvoretsky (almost all his books, mainly ...Play series), Seirawan (...Winning series) Chernev (for his amazing enthusiasm) and Nunn.