Stepanov, T. (2020) “The History and Culture of Bulgaria in the 7th–12th Centuries: Between Two Easts and Two Wests”, in Brzozowska, Z.A. et al. (eds.) Phantom of Muhammad, Shade of Samuel Byzantine Empire in Relation to Members of Other Cultures and Religions (7th–15th c.): No. XXXIX. Poland: Lodz University Press (Byzantina Lodziensia), pp. 163–176. doi:10.18778/8142-804-0.08.