Hacking Exposed Linux: Linux Security Secrets and Solutions by Isecom

How Linux Works, 3rd Edition: What Every Superuser Should Know Paperback

How Linux Works, 3rd Edition: What Every Superuser Should Know

ISSA Ethical Hacking: Techniques, Tools, and Countermeasures 3rd Edition

Linux Command Line 3rd Edition - GOOD

Hacking Exposed: Network Security Secrets & Solutions - 3rd Edition w/CD

Gray Hat Hacking The Ethical Hackers Handbook, 3rd Edition - VERY GOOD

Red Hat Linux Secrets 3rd edition plus Linux Programing Unleased