http://www.tldp.org
http://www.tldp.org/links/../index.html
http://www.tldp.org/links/../docs.html#howto
http://www.tldp.org/links/../guides.html
http://www.tldp.org/links/../docs.html#faq
http://www.tldp.org/links/../docs.html#man
http://www.tldp.org/links/../docs.html#lg
http://www.tldp.org/links/../docs.html#lf
http://writers.fultus.com/garrels/
http://www.fultus.com/
http://www.openna.com/
http://www.opendocspublishing.com/
http://www.sybex.com
http://www.tldp.org/links/../guides.html#securing_linux
http://www.oreilly.com/catalog/linag2/
http://www.oreilly.com/