Dragan on Security

Here: Rare 17th Century work on Cryptography.

Title: Cryptomenytices et cryptographiae libri IX. In quibus & planissima Steganographiae à Johanne Trithemio, abbate Spanheymensi & Herbipolensi, admirandi ingenij viro, magicè & aenigmaticè olim conscriptae, enodatio traditur. Inspersis ubiquè authoris ac aliorum, non contemnendis inventis…

Author: Selenus, Gustavus [pseud. of August, Duke of Braunschweig-Luneburg]