Author
- Peter Olivi1
- Peter Paludanus1
- Philip the Chancellor1
- Pierre Mathieu1
- Pierre Mésenge1
- Pierre de La Cépède1
- Pietro Marcello1
- Pius II1
- Pseudo Bernard of Clairvaux1
- Pseudo-Andronicus of Rhodes1
- Pseudo-Cicero1
- Pseudo-Prosper1
- Quintus Aurelius Symmachus1
- Quodvultdeus1
- Rabanus Maurus1
- Ricardus, de Mediavilla, approximately 1249-1308?1
- Richard de Saint-Laurent1
- Robert Grosseteste1
- Robert Holkot1
- Robert Kilwardby1