Educational magazines
- Odell, Jonathan
- Olympic Sports Technical Performance Rules and Glossary of Techniques United States Olympic Committee (USOC) (2000)
- On the Brink of War (1770–1774)
- Paper Dinosaurs: A Hypertext Catalog of Rare Documents (1824–1969)
- Pascual Cervera y Topete
- Peace Is Promised, But War Continues
- Peace, But at What Cost
- Pike, Catherine "Renee" Young
- Ramsay, David
- Reactions to War's End from the Front
- Redfield Proctor
- Reed, Esther de Berdt
- Reluctant Warriors: The United States in World War I
- Resolves of the House of Representatives …
- Richard Stumpf
- Riedesel, Frederika von
- Rivington, James
- Rosa Luxemburg
- Rush, Benjamin
- Sam Houston