Columbia subject headings:
Merchant marine--Europe--History.
Merchant marine--South Africa--History.
Shipping conferences--History.
Union-Castle Mail Steamship Company--History.
Harvard subject headings:
Merchant marine--Europe--History.
Merchant marine--South Africa--History.
Shipping conferences--History.
Union-Castle Mail Steamship Company--History.
Princeton subject headings:
Merchant marine--Europe--History.
Merchant marine--South Africa--History.
Shipping conferences--History.
Union-Castle Mail Steamship Company--History.