Ubuntu Linux Toolbox by Christopher Negus

Linux for Programmers and Users

Fedora Linux Toolbox: 1000+ Commands for Fedora, CentOS and Red Hat Power Users

Understanding the LINUX Kernel: From I/O Ports to Process Management - GOOD

Linux Bible - Paperback By Negus, Christopher - VERY GOOD

Linux For Dummies, 9th Edition by Richard Blum

Fedora Linux Toolbox: 1000+ Commands for Fedora, CentOS and Red Hat Power Users,

Ubuntu Linux Toolbox: 1000+ Commands for Ubuntu and Debian Power