- Ohio Student Association 1
- Ohio Valley History1
- Oliver Peirce 1
- Osnabrück, Druck von J.H. Ebering, 1868-18721
- Otis, Broaders & Co.1
- Paris : Chez Du Pont, l'an III de la République [1795]1
- Parker, A.1
- Perkins & Marvin1
- Peterson, Robert E., 1812-18692
- Phillips, C., 1970, Smithsonian, 1(3):41, photo in color, by W. K. Sacco1
- Phytokeys1
- Plot Politics2
- Plowman, Thomas Lowry1
- Pomeroy, Ralph Wheelock, 1792-18441
- Potter, Paraclete, 1784-18581
- Powers, O. M. (Orville Marcellus), 1852-1
- Pratt, James W.1
- Pratt, Woodford & Co. 7
- Preventing School Failure1
- Public-School Publishing Company1