Letter from Ḵalfa b. Isḥāq b. Menaḥem to Abū Yaḥyā Nahray b. Nissīm, who added a note at the end of the text.
Goitein (1973: 146-147); Gil (1997: III 852-4).
"The original materials are currently held at Cambridge University, on a long-term loan until 2026.".
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