- *Mr. Root and Mr. Brand, in Washington: Letters and Sketches Dealing with Their Political Pilgrimage as Members of the Indiana Congressional League; and, Their Brief Sojourn at the Capital* (1906)
- *The Development of the League of Nations Idea: Documents and Correspondence of Theodore Marburg* (1932)
Articles:
- "The League of Nations: What It Is and What It Is Not" (1918)
- "The League of Nations: A Commentary on the Covenant" (1919)
- "The League of Nations: A Constructive Criticism" (1920)
- "The League of Nations: A Review of Its Work" (1922)
- "The League of Nations: A Defense" (1923)
- "The League of Nations: A Retrospect and a Prospect" (1924)