Rosenberg, Daniel K., Lynn A. Trulio, Daniel H Catlin, Deborah Chromczack, Jennifer A. Gervais, Noelle Ronan, and Katherin A. Haley. 2007. Unpublished synthesis report to the BLM.
download at: http://www.oregonwildlife.org/species-at-risk/burrowing-owl-research-and-conservation