Old Bulgarian
| Author(s) | Title | Reference | |
|---|---|---|---|
| Thomas M. Parker | The Bogomils: a study in Balkan Neo-Manichæism, by Dmitri Obolensky | 18/, p. 68 | |
| Anthony Gervase Mathew | The Byzantine Commonwealth: Eastern Europe 500-1453, by Dimitri Obolensky | 42/3, p. 302 |