Administrating Solr
Surendra Mohan
Apache Security
Ivan Ristic
The Sign of the Four
Arthur Conan Doyle
The Linux Programming Interface
Michael Kerrisk
The Book of PF: A No-Nonsense Guide to the OpenBSD Firewall
Peter N. M. Hansteen
Absolute FreeBSD: The Complete Guide to FreeBSD, 2nd Edition
Michael W. Lucas