Ask HN: Older textbooks/papers you consider classics still worth studying today?
Claude Shannon's original 1948 paper "A Mathematical Theory of Communication" launched the entire field of information theory.  It's 50 pages, highly readable, and pedagogical.  The source of its magic is that Shannon introduces and concretely grounds an essentially new ontological concept of vast applicability.  And it has <i>100,000 citations</i>.<p><a href="http://math.harvard.edu/~ctm/home/text/others/shannon/entropy/entropy.pdf" rel="nofollow">http://math.harvard.edu/~ctm/home/text/others/shannon/entrop...</a>