books by subject
Computing Certifications
Unix and Linux Answers!: Certified Tech Support (Osborne's answers!: certified tech support)
Solaris Administration: A Beginner's Guide (Network Professional's Library)
Security in Fixed and Wireless Networks: An Introduction to Securing Data Communications
Foundations of Software Testing: ISTQB Certification: Edition Updated for ISTQB Foundation
RHCE Red Hat Certified Engineer Study Guide