Petrus
| Author(s) | Title | Reference | |
|---|---|---|---|
| Paul Piehler | Studien zum Locus Amoenus im Mittelalter. (Wiener Romanistische Arbeiten X), by Dagmar Thoss | 44/3, p. 290 | |
| MICHAEL SHIELDS | The 'Summa musice': A Thirteenth-Century Manual for Singers, by Christopher Page | 63/2, p. 309 | |
| James Simpson | Langland's Fictions, by J. A. Burrow | 63/2, p. 328 |