Columbia subject headings:
Harvard subject headings:
California, Gulf of (Mexico)--Description and travel.
Marine invertebrates--Mexico--California, Gulf of.
Ricketts, Edward Flanders, 1897-1948.
Steinbeck, John, 1902-1968
Princeton subject headings:
California, Gulf of (Mexico)--Description and travel.
Marine invertebrates--Mexico--California, Gulf of.
Ricketts, Edward Flanders, 1896-1948--Travel--Mexico--California, Gulf of.
Steinbeck, John, 1902-1968--Travel--Mexico--California, Gulf of.