Book bears copyright notice "Copyright 1960 by the Associated Students, University of California, Los Angeles", but no evidence of renewal was found (tried various searches at [1] including: title "southern campus"; name "associated students"; keywords "university of california" AND "yearbook"; keywords "university of california" AND "1960"). Labeled as "not in copyright" by University of California Libraries on archive.org page.
Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (70 years p.m.a.), Mainland China (50 years p.m.a., not Hong Kong or Macao), Germany (70 years p.m.a.), Mexico (100 years p.m.a.), Switzerland (70 years p.m.a.), and other countries with individual treaties.