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Linux essentials, 2nd edition
Ubuntu Linux toolbox - 1000 + commands for power users, second edition
Linux all-in-one for dummies, 6th edition
Beginning Linux programming, fourth edition

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Lenox Bible, 9th edition
shell scripting - expert recipes for Linux, bash, and more
Linux server security - hack and defend
CompTIA Linux+ and LPIC practice tests: Exams LX0-103/LPIC-1 101-400, LX0-104/LPIC-1 102-400, LPIC-2 201, and LPIC-2 202
Professional Linux kernel architecture

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Linux command line and shell scripting Bible, third edition
CompTIA Linux+ powered by Linux professional institute study guide: exams LX0-104 and LX0-104, 3rd edition
LPIC-1: Linux professional institute certification study guide: exams 101 and 102, 4th edition
LPIC-2: Linux professional institute certification study guide: exams 201 and 202, 2nd edition
Red hat Enterprise Linux 6 administration - real-world skills for redhat administrators
Assembly language step by step - programming with Linux, 3rd edition

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