Columbia subject headings:
Americans--Protection--Foreign countries.
International business enterprises--Security measures.
Non-governmental organizations--Security measures.
Terrorism--Prevention.
Harvard subject headings:
Americans--Protection--Foreign countries.
International business enterprises--Security measures.
Non-governmental organizations--Security measures.
Terrorism--Prevention
Princeton subject headings:
Americans--Protection--Foreign countries.
International business enterprises--Security measures.
Non-governmental organizations--Security measures.
Terrorism--Prevention.