Varady, R.G., H. Ingram, and L. Milich. 1995. The Sonoran Primeria Alta: Shared environmental problems and challenges, Journal of the Southwest 37(1):102-22.
Surveys the shared environmental problems of the Arizona-Sonora border region, with special attention to Colorado River salinity, the Rio Sonoyta and Organ Pipe Cactus National Monument, the San Pedro River and Riparian National Conservation Area, and the Ambos Nogales area. Reveals the history of institutional challenges and responses to local drought and flood-related problems, and presents strategies for the future of local cooperative environmental management.