T-S AS 145.139
Letter addressed to Natan b. Yiftaḥ. In Judaeo-Arabic. Mentioning a circumcision conducted by the sender, the cantor Elʿazar ha-Kohen, someone called Rosh ha-Qahal al-Zariz, ritual slaughtering, Sayyidnā, and Rabbenu ha-Rav ha-Gadol. The sender is probably a provincial muqaddam or aspiring muqaddam campaigning for recognition from the authorities in Fustat. (Information in part from CUDL)