Raymond, Eric S.; MIT Press; 1996; ISBN 0-262-68092-0; 547pp.
Um, er. A guide to Internet culture. Lots of people like it. HTML at the Jargon File Resource Page.
Salus, Peter H.; Addison-Wesley; 1994; ISBN 0-201-54777-5; 256pp.
Linux is part of the Unix tradition. This book is an oral history of Unix -- how it originated, how it evolved, how it spread -- by the people who were there.
Brooks, Frederick P.; Addison-Wesley 1995 (ISBN 0-201-83595-9).
The one book on software engineering that everyone should read.
Alan Cox: "This I'd recommend not for its technical value but for its application of common sense and reality to computing projects." JH: "Ah, yes. What if Linus had been given 200 programmers and had been told to produce Linux in 3 months!"
AT&T; 416 pp.
Many early papers on Unix, including Ritchie & Thompson, "The UNIX Time Sharing System"; Thompson, "UNIX Implementation"; Ritchie, "A Retrospective"; Bourne, "The UNIX Shell"...