Columbia subject headings:
Harvard subject headings:
Hijacking of ships--Africa, Southern--Prevention.
Maritime terrorism--Africa, Southern--Prevention.
Shipping--Africa, Southern--Security measures.
Shipping--Security measures--Africa, Southern.
Princeton subject headings:
Hijacking of ships--Africa, Southern--Prevention.
Maritime terrorism--Africa, Southern--Prevention.
Merchant marine--Africa, Southern--Security measures.
Shipping--Africa, Southern--Security measures.