There are both site-specific and synthesis reports on groups of Italian-Swiss
who occupied the Diamond/Domenigoni valleys in Riverside County, CA.  They
include  family histories, excavation reports, stone architecture, etc.  They
are (or should be) available from Metropolitan Water District of Southern
California.  Contact Dennis Majors,  or Wendy Picht, MWD,  PO Box 54153, Los
Angeles 90054-0153.
Roberta Greenwood