Columbia subject headings:
Asia--Commerce--History.
Merchant marine--Indian Ocean Region--History.
Merchant marine--Persian Gulf Region--History.
Merchant marine--South China Sea Region--History.
Navigation--Asia--History.
Harvard subject headings:
Asia--Commerce--History.
Merchant marine--Indian Ocean Region--History.
Merchant marine--Persian Gulf Region--History.
Merchant marine--South China Sea Region--History.
Navigation--Asia--History.
Princeton subject headings:
Businessmen--China Sea--History.
Businessmen--Indian Ocean--History.
Merchants--China Sea--History.
Merchants--Indian Ocean--History.