https://en.wikipedia.org/wiki/Solitaire_(cipher) https://en.wikipedia.org/wiki/Solitaire_(cipher) "The Solitaire cryptographic algorithm was designed by Bruc

https://en.wikipedia.org/wiki/Solitaire_(cipher) https://en.wikipedia.org/wiki/Solitaire_(cipher) "The Solitaire cryptographic algorithm was designed by Bruce Schneier at the request of Neal Stephenson for use by field agents in his novel Cryptonomicon, enabling them to communicate securely without having to rely on electronics or having to carry incriminating tools, It was designed to be a manual cryptosystem calculated with an ordinary deck of playing cards. In Cryptonomicon, this algorithm was originally called Pontifex to hide the fact that it involved playing cards."