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 * [A Method for Obtaining Digital Signatures and Public-Key Cryptosystems](http://people.csail.mit.edu/rivest/Rsapaper.pdf)
 * [Twenty Years of Attacks on the RSA Cryptosystem](https://crypto.stanford.edu/~dabo/papers/RSA-survey.pdf)
+* [Communication Theory of Secrecy Systems](communication-theory-of-secrecy-systems.pdf)
+
+## Related Works
+### [A Mathematical Theory of Cryptography (1945)](http://www.cs.bell-labs.com/who/dmr/pdfs/shannoncryptshrt.pdf) - Shannon
+The original classified memo for Bell Labs that was republished in 1949 as ["Communication Theory of Secrecy Systems"](communication-theory-of-secrecy-systems.pdf).
+
+### [A Mathematical Theory of Communication (1948)](../information_theory/a-mathematical-theory-of-communication-1948.pdf) - Shannon
+Shannon said that his wartime insights into communication theory and cryptography developed simultaneously and that "they were so close together you couldn’t separate them". ["Communication Theory of Secrecy Systems"](communication-theory-of-secrecy-systems.pdf) incorporates many concepts and formulations that also appeared in his 1948 paper.
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