• The Inevitability of Failure: The Flawed Assumption of Security in Modern Computing Environments explains the need for mandatory access controls.
• The Flask Security Architecture: System Support for Diverse Security Policies explains the security architecture of Flask, the architecture used by SELinux.
• Implementing SELinux as a Linux Security Module has specifics about SELinux access checks in the kernel.

• Configuring the SELinux Policy
• SELinux Reference Policy
• SELinux Object Classes and Permissions Overview

• SELinux by Example: Using Security Enhanced Linux, Frank Mayer, Karl MacMillan, and David Caplan, Prentice Hall, 2006; ISBN 0131963694
• SELinux: NSA's Open Source Security Enhanced Linux, Bill McCarty, O'Reilly Media, 2004; ISBN 0596007167

The following resources are specific towards Gentoo Hardened's SELinux implementation.

• SELinux Frequently Asked Questions