Appreciation is extended to the United States Department of the Interior, Lic. Bernardo Biados, the Barry Fells and various government agencies in the Americas for their assistance in accessing photographed sites. The sources of unidentified photos are being sought; please contact <firstname.lastname@example.org>
Further details about sites may be found in:
Heizer, R. F. & M. A. Baumhoff. 1962. Prehistoric Rock Art of Nevada and Eastern California. Univ. of Calif. Press, Berkeley, Los Angeles, London. 412 p. and <Bibliography>
The ancient originators of the structures and art displayed are posthumously respectfully acknowledged. For teaching purposes; quote cited references when available.