Penetration Testing: A Hands-On Introduction to Hacking
Gorgia Weidman
Serious Cryptography
Jean-Philipee Aumasson
The Hardware Hacker
Andrew Bunnie Huang
Linux Device Drivers
Jonathan Corbet & Alessandro Rubini & Greg Kroah-Hartman
Bash Cookbook
Carl Albing & JP Vossen
grep Pocket Reference
John Bambenek & Agnieszka Klus
Linux Pocket Guide
Daniel J. Barrett
Linux System Programming
Robert Love
Linux Basics for Hackers
OccupyTheWeb
Unix Power Tools
Shelley Powers
Effective Awk Programming
Arnold Robbins
Classic Shell Scripting
Arnold Robbins & Nelson H. F. Beebe
The Linux Command Line, 2nd Edition
William Shotts
Linux in a Nutshell
Ellen Siever & Stephen Figgins & Robert Love & Arnold Robbins
Cybersecurity Ops with bash
Paul Troncone & Carl Albing Ph.D.