Jenkins, Romilly James Heald.De Administrando Imperio by Constantine VII Porphyrogenitus (англ.). — New, revised. — Washington, D.C.: Dumbarton Oaks Center for Byzantine Studies, 1967. — P. 65. — (Corpus fontium historiae Byzantinae). — ISBN 0-88402-021-5. According to Constantine Porphyrogenitus, writing in his De Administrando Imperio (ca. 950 AD) «Patzinakia, the Pecheneg realm, stretches west as far as the Siret River (or even the Eastern Carpathian Mountains), and is four days distant from Tourkia (i.e. Hungary).»
Öztürk, ÖzhanPontus: Antik Çağ'dan Günümüze Karadeniz'in Etnik ve Siyasi Tarihi (неопр.) 364 (2011). — «... Greek term Tourkoi first used for the Khazars in 568 AD. In addition in "De Administrando Imperio" Hungarians call Tourkoi too once known as Sabiroi ...» Дата обращения: 4 июня 2022. Архивировано 13 октября 2016 года.
Öztürk, ÖzhanPontus: Antik Çağ'dan Günümüze Karadeniz'in Etnik ve Siyasi Tarihi (неопр.) 364 (2011). — «... Greek term Tourkoi first used for the Khazars in 568 AD. In addition in "De Administrando Imperio" Hungarians call Tourkoi too once known as Sabiroi ...» Дата обращения: 4 июня 2022. Архивировано 13 октября 2016 года.