- University Professor, History
- Modern Germany; European Diplomatic History
Editor, Handbooks on European Diplomatic History, 1918-1945. 5 vols. (1981-84). Second edition, 7 vols., 1991.
German Foriegn Policy, 1918-1945: A Guide to Research and Research Materials. Scholarly Resources, Inc., Wilmington, Del., 1981. Second edition, revised and enlarged, 1991
Germany and the League of Nations (1976)
The Free City: Danzig and German Foreign Policy 1919-1934 (1968)
- "Trawling for Leaders: Campus Leadership Development at Brooklyn College." Liberal Education, November/December 1992
- "Germany and the League of Nations." The League of Nations in Retrospect", Berlin/New York, 1983