Sefer ko'aḥ ha-avanim = On the virtue of the stones : Hebrew text and English translation : with a lexicological analysis of the romance terminology and source study / Berakhyah Ben Natronai ha-Nakdan ; edited, translated, and annotated by Gerrit Bos and Julia Zwink.
Berechiah ben Natronai, ha-Nakdan, active 12th century-13th century. | Date: 2010