Bibliography : Fire Stones
| Ron Baxter; Colum Hourihane, ed. | Learning from Nature: Lessons in Virtue and Vice in the Physiologus and Bestiaries |
| Arthur H. Collins | Symbolism of Animals and Birds Represented in English Church Architecture |
| Michael J. Curley | Physiologus |
| Victor Henry Debidour | Le Bestiaire Sculpté du Moyen Age en France |
| Debra Hassig | Homo animal est, homo animal non est: Text and Image in Medieval English Bestiaries |
| Leo Wiener | Contribution Towards a History of Arabico-Gothic Culture, Volume IV: Physiologus Studies |