20200611 19565700 1.0 TRUE Trade Relations Trade relations among indigenous cultural groups in California as recorded by ethnographers in the 19th and 20th centuries.Source:James T. Davis, "Trade Routes and Economic Exchange Among the Indians of California.” University of California Archeological Survey No. 54, 1961. University of California, Berkeley Library (JTD1961).For more information see: nahc.ca.gov/cp/references/ See nahc.ca.gov/cp/references/