Tertiary sources are sources that identify and locate primary and secondary sources. These can include bibliographies, indexes, abstracts, encyclopedias, and other reference resources; available in multiple formats, i.e. some are online, others only in print.
It is important to note that these categories, i.e. secondary and tertiary, are not mutually exclusive. A single item may be primary or secondary (or even tertiary) depending on your research topic and the use you make of that item.
Barrett, Ellen C.
Baja California; a bibliography of historical geographical, and scientific literature relating to the peninsula of Baja California and to the adjacent islands in the Gulf of California and the Pacific Ocean.
Los Angeles, Bennett & Marshall, 1957-67.
Berry, Roger B.
Centennial bibliography of Orange County California / compiled by
Roger B. Berry and Sylvester E. Klinicke ; edited by Shirley E. Stephenson and Roger Berry ; managing editor, Louise Booth.
Santa Ana, Calif. : Orange County Historical Society, 1989.
A guide to the oral history collection of Cambodians in California / Charles Martell, Kitty W. Shek.
Sacramento, CA : The Library, California State University, c1992.
Kurutz, Gary F.
The California Gold Rush : a descriptive bibliography of books and pamphlets covering the years 1848-1853 / by Gary F. Kurutz ; introduction by J.S. Holliday.
San Francisco : Book Club of California, 1997.