Bash Pocket Reference
Arnold Robbins
Time Management for System Administrators
Thomas A. Limoncelli
Understanding Bitcoin: Cryptography, Engineering and Economics
Pedro Franco
Ipv6 Essentials
Silvia Hagen
PostgreSQL 9 High Availability Cookbook
Shaun M. Thomas
Hack and HHVM: Programming Productivity Without Breaking Things
Owen Yamauchi
Apache Solr High Performance
Surendra Mohan