Rav Nachman bar Yitzchak (d. 356), disciple of Abaye and Rava was dean of the Yeshiva at Pumbedita. In his youth, Rav Nachman studied together with Rava, but he sat one row behind him. Later Rav Nachman studied under Rav Chisda. During the time when Rav Joseph bar Chiya was head of the Yeshivah of Pumbeditha and Rava conducted his own Yeshivah in Mechoza, Rav Nachman bar Yitzchak was the chief lecturer (Resh Kalah) under Rava, … Wikipedia
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