Author
- Priscian1
- Pseudo Bernard of Clairvaux1
- Pseudo-Andronicus of Rhodes1
- Pseudo-Cicero1
- Ptolemy1
- Rafaino Caresini1
- Ralph of Longchamp1
- Rashi1
- Rashid-al-Din Hamadani1
- Republic of Venice1
- Richard Maidstone1
- Richard Rolle1
- Richard of Middleton1
- Robert Gazeley1
- Robert Holkot1
- Robert Kilwardby1
- Robert de Sorbon1
- Robert of Gloucester1
- Roffredo Epifanio1
- Roman Catholic Archdiocese of Siena1