Tyszkiewicz, L. A. (1999) “Ethnic transformations in the Lower and Middle Danube in the 2nd part of the 6th century on the basis of the fragments of „History” by Menander the Protector”, Balcanica Posnaniensia. Acta et studia, (9/10), pp. 31–48. doi: 10.14746/bp.1999.9-10.4.