There is a scholarly theory that he may have been the same person asBezmer[4] of theNominalia of the Bulgarian khans who may have been also the first son ofKubrat.[5] He was a member of theDulo clan, who after Kubrat's death in the mid-7th century ruledOld Great Bulgaria, but his rule lasted only three years.[6]Kevin Alan Brook calls him Bayan.[7] Batbayan would subsequently have ruled the Bulgars as a subject of the Khazar Khagan.
^Dinkov, Stoyan (2018). Radev, Radoslav (ed.).Османо – Римска империя, българи и тюрки (in Bulgarian) (2 ed.). Sofia: Uncorp.org. Retrieved21 August 2023.Каганите стават балтавари: Бат-Баян Дуло (667–690), Бу-Тимер (690–700), Сулоби (700–727), [...].
^Boris Zhivkov, Khazaria in the Ninth and Tenth Centuries, East Central and Eastern Europe in the Middle Ages, 450-1450, BRILL, 2015,ISBN9004294481, p. 138 & 228-229.
^Carl Waldman, Catherine Mason, Encyclopedia of European Peoples, Facts on File library of world history, Infobase Publishing, 2006,ISBN1438129181. pp. 106-197.
^Boris Zhivkov, Khazaria in the Ninth and Tenth Centuries, East Central and Eastern Europe in the Middle Ages, 450-1450, BRILL, 2015,ISBN9004294481, p. 228.
^Florin Curta, Roman Kovalev as ed., "'The' Other Europe in the Middle Ages: Avars, Bulgars, Khazars and Cumans", Volume 2 of East Central and Eastern Europe in the Middle Ages, 450 - 1450, BRILL, 2008,ISBN9004163891, p. 152.
^Vasil Gyuzelev, The Proto-Bulgarians: Pre-history of Asparouhian Bulgaria, Sofia Press, 1979, p. 29.
