Rabbi Elazar, the father of Rabbi Yitzchak bar Nachman [in the name of Rabbi Hoshaya, Jerusalem Talmud, Peah 1:2; however, there is a textual error: if he is the son of Nachman, how is Rabbi Elazar his father? Perhaps it should be "brother"].
Seder_HaDorot,_Tanaim_and_Amoraim.553:1