Abba bar Dudai was head of the Academy of Pumbedita (at the time within the Abbasid Caliphate) from 772 till about 780 CE. Sherira Gaon adds to Abba's name the words "our grandfather," which, however, are not meant to indicate that Dudai was an immediate ancestor of Sherira. A copyist's attempt to change the rare name "Dudai" into "Judai" adds to the confusion; for Judai Gaon, the actual grandfather of Sherira, lived a full century later than Dudai.

References

 This article incorporates text from a publication now in the public domain: Singer, Isidore; et al., eds. (1901–1906). The Jewish Encyclopedia. New York: Funk & Wagnalls. {{cite encyclopedia}}: Missing or empty |title= (help)