Yehudai ben Nahman or Yehudai Gaon was the head of the yeshiva in Sura from 757 to 761, during the Gaonic period of Judaism. He was author of the book "Halachot Pesukot", which discusses those halachot that were practiced in the Diaspora since the destruction of the Second Temple. The text, which is generally organized along the same pattern as the tractates of the Babylonian Talmud, was the subject of many abridgements and summaries. Wikipedia
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