Columbia subject headings:
Harvard subject headings:
Mercedes (Frigate)--Exhibitions.
Shipwrecks--Portugal--Algarve--Exhibitions.
Spain. Armada--History--19th century--Exhibitions.
Underwater archaeology--Portugal--Algarve--Exhibitions.
Princeton subject headings:
Mercedes (Frigate)--Exhibitions.
Shipwrecks--Portugal--Algarve--Exhibitions.
Spain. Armada--History--19th century--Exhibitions.
Underwater archaeology--Portugal--Algarve--Exhibitions.