Essential System Administration
Æleen Frisch
Digital Forensics and Incident Response
Gerard Johansen
Malware Analyst's Cookbook and DVD
Michael Ligh, Steven Adair, Blake Hartstein, Matthew Richard
Nmap: Network Exploration and Security Auditing Cookbook
Paulino Calderon
CCNA 200-301 Official Cert Guide Library
Wendell Odom & Jason Gooley & David Hucaby