Princeton University Press · University of California Press
| title | media type | ISBN-13 (ISBN-10) | year of publication |
|---|---|---|---|
| Two Churches: England and Italy in the Thirteenth Century | Paperback | 978-0-520-06098-2 (0-520-06098-9) | 1988 |
| Two Churches: England and Italy in the Thirteenth Century | Hardcover | 978-0-691-07141-1 (0-691-07141-1) | 1968 |