Ladewig Petersen E. Irving A. Agus: Urban Civilization in Pre-Crusade Europe. A Study of Organized Town-Life in Northwestern Europe during the Tenth and Eleventh Centuries basedon the Responsa Literature. Vols. I—II. Leiden, E. J. Brill, 1965. xii + 420 s., vi + 401 s. 54 fl. ht [Internet]. 1. januar 1967 [henvist 26. april 2024];12. Tilgængelig hos: https://tidsskrift.dk/historisktidsskrift/article/view/50731