APA-ийн эшлэл(7 дахь хэвлэлт)

Petkov, K. (2008). The voices of medieval Bulgaria, seventh-fifteenth century: The records of a bygone culture. Brill.

Чикаго-гийн эшлэл (17 дахь хэвлэлт)

Petkov, Kiril. The Voices of Medieval Bulgaria, Seventh-fifteenth Century: The Records of a Bygone Culture. Leiden ; Boston [Mass.]: Brill, 2008.

MLA -ийн эшлэл (9 дэх хэвлэлт)

Petkov, Kiril. The Voices of Medieval Bulgaria, Seventh-fifteenth Century: The Records of a Bygone Culture. Brill, 2008.