Rudenko , K. A. “Material Culture of the Volga Bolgars in the Scientific Works by A.P. Smirnov”. Arkheologiia Evraziiskikh Stepei (Archaeology of the Eurasian Steppes), no. 6, Dec. 2023, pp. 249-58, doi:10.24852/2587-6112.2023.6.249.258.