diff --git a/free-programming-books.md b/free-programming-books.md
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@@ -554,7 +554,7 @@ Original Source: [Free Programming books](http://stackoverflow.com/revisions/392
 * [OWASP Top 10 for .NET Developers](http://www.troyhunt.com/2011/12/free-ebook-owasp-top-10-for-net.html)
 * [Security Engineering](http://www.cl.cam.ac.uk/~rja14/book.html)
 * [CryptoParty Handbook](https://www.cryptoparty.in/documentation/handbook)
-
+* [OpenSSL Cookbook](https://www.feistyduck.com/library/openssl-cookbook/)
 
 #### Software Architecture
 * [Architectural Styles and the Design of Network-based Software Architectures](http://www.ics.uci.edu/~fielding/pubs/dissertation/top.htm) - Roy Thomas Fielding