1. Columbia University Rare Book & Manuscript Library, MS X893 Z8 v.2 no.3 DS ID: DS18606 Title: Responsa Author: Ishmael ben Abraham Isaac ha-Kohen Place: Italy Date: 17--
2. Columbia University Rare Book & Manuscript Library, MS X893 Is3 DS ID: DS18773 Title: Hebrew texts Author: Ishmael ben Abraham Isaac ha-Kohen Place: Italy Date: 17--