APA-viite (7. p.)
Williamson, M. (2011). pfSense 2 cookbook: A practical, example-driven guide to configure even the most advanced features of pfSense 2. Packt Open Source.
Chicago-viite (17. p.)
Williamson, Matt. PfSense 2 Cookbook: A Practical, Example-driven Guide to Configure Even the Most Advanced Features of PfSense 2. Birmingham, U.K.: Packt Open Source, 2011.
MLA-viite (9. p.)
Williamson, Matt. PfSense 2 Cookbook: A Practical, Example-driven Guide to Configure Even the Most Advanced Features of PfSense 2. Packt Open Source, 2011.
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