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<h2 id="references">References</h2> <ol> <li id="fn:1"><p>Zlatarski, Vasil N. (1918). Medieval History of the Bulgarian State, Vol I: History of the First Bulgarian Empire, Part I: Age of Hun-Bulgar Domination (679-852) (in Bulgarian). Sofia: Science and Arts Publishers, 2nd Edition (Petar Petrov, Ed.), Zahari Stoyanov Publishers, 4th Edition, 2006. ISBN 954-739-928-4. {{cite book}}: ISBN / Date incompatibility (help) <a href="954-739-928-4" target="_blank">954-739-928-4</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Runciman, Steven (1930). A History of the First Bulgarian Empire. G. Bell & Sons, London. <a href="/wiki/Steven_Runciman" target="_blank">/wiki/Steven_Runciman</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> </ol>