Open Game License v 1.0a © 2000, Wizards of the Coast, Inc.
System Reference Document © 2000, Wizards of the Coast, Inc.; Authors: Jonathan Tweet, Monte Cook, and Skip Williams, based on material by E. Gary Gygax and Dave Arneson.
Pathfinder Campaign Setting: Path of the Hellknight © 2016, Paizo Inc.; Author: F. Wesley Schneider.