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 U.S. Fish and Wildlife Service. 1998. Endangered Status for the Peninsular Ranges Population Segment of the Desert Bighorn Sheep in Southern California. Federal Register, March 18, 1998 (63 FR 13134).
 U.S. Fish and Wildlife Service. 2000. Recovery Plan for bighorn sheep in the Peninsular Ranges, California. Portland, OR. 251 pp.