Absolute OpenBSD: Unix for the Practical Paranoid, Michael W. Lucas, Book

The Ksh, Awk, And Sed Script Collection: Mastering Unix Programming Through...

UNIX and Linux System Administration Handbook by Ben Whaley, Garth Snyder,...

C Library Reference for UNIX System V.4 (with ANSI C)

UNIX: An Open Systems Dictionary - Over 6,000 jargon-free definitions

Using C with Curses, Lex and Yacc : Building a Window Shell for UNIX System V by

The Unix C Shell Field Guide - Paperback By Gail Anderson - GOOD

Harley Hahn's Student Guide to Unix by Harley Hahn (1996, Trade Paperback)