Harvard University | Harvard | ATP International Series | World Trade Center | center | International Monetary Fund | Harvard Business School | Harvard Medical School | International Red Cross and Red Crescent Movement | ATP International Series Gold | International Space Station | Harvard College | Amnesty International | Harvard Law School | International Olympic Committee | BirdLife International | International Finance Corporation | International Organization for Standardization | International Telecommunication Union | International Criminal Court | One Day International | International Nonproprietary Name | International Labour Organization | Kennedy Space Center | International Civil Aviation Organization | International Boxing Federation | Toronto International Film Festival | International Atomic Energy Agency | United States Department of Veterans Affairs | International Maritime Organization |
In 1968 he was invited by Henry Kissinger to teach at the Harvard Center for International Affairs, and the following year, he was appointed as Professor at the Free University of Berlin, where he taught until his retirement in 1998.