''Mina Yang offers a musical message of social hope without stepping back from fierce historical inequities. California Polyphony will sit on my bookshelf between Mike Davis's City of Quartz and George Lipsitz's Dangerous Crossroads.'' Deborah Wong, author of Speak It Louder: Asian Americans Making Music ''A landscape of California's musical history. This welcome addition to music and cultural studies combines the musical contributions of African Americans, East Asian Americans, and Mexican Americans in a unique and refreshing way.'' Cheryl L. Keyes, author of Rap Music and Street Consciousness