Biggs, T.H, R.S. Leighty, S.J. Skotnicki, P.A. Pearthree, T.R. Orr, and S.M. Richard. 1999. Digital Map of the Geology, Geomorphology, and Soils of the San Bernardino Valley, Southeastern Arizona. DI-15 Version 1.0.

• soil
• Arizona
• GIS
• San Bernardino Valley