OQ AND OĞUR ~ OĞUZ*, Peter B. Golden, бележка 37Archiviato il 19 aprile 2015 in Internet Archive., ... but a Dulo-Dulu connection, however appealing as a legitimating source for Bulğar kingship, cannot be established on the basis of our current data.
Васил Н. Златарски, История на Първото българско царство. I. Епоха на хуно-българското надмощие (679—852), su promacedonia.org
web.archive.org
OQ AND OĞUR ~ OĞUZ*, Peter B. Golden, бележка 37Archiviato il 19 aprile 2015 in Internet Archive., ... but a Dulo-Dulu connection, however appealing as a legitimating source for Bulğar kingship, cannot be established on the basis of our current data.