| Principles of literary criticism
I. A. Richards | |
| Principles of Mining: Valuation, Organization and Administration
Herbert Hoover | |
| Principles of Orchestration, with Musical Examples Drawn from His Own Works
Nikolay Rimsky-Korsakov | |
| Principles of politeness, and of knowing the world
Earl of Philip Dormer Stanhope Chesterfield | |
| Principles of Political Economy
Arthur Latham Perry | |
| Principles of Political Economy / Abridged with Critical, Bibliographical, and Explanatory Notes, and a Sketch of the History of Political Economy
John Stuart Mill | |
| Principles of Political Economy, Vol. 1
Wilhelm Roscher | |
| Principles of Political Economy, Vol. 2
Wilhelm Roscher | |
| Principles of Public Health / A Simple Text Book on Hygiene, Presenting the Principles Fundamental to the Conservation of Individual and Community Health
Thomas Dyer Tuttle | |
| Principles of Teaching
Adam S. Bennion |
