@book{ 0-1180764005, title = {Dzieje i kultura dawnych Słowian (do X wieku)}, author = {Gąssowski, Jerzy}, address = {Warszawa}, publisher = {Pánstwowe Zakł. Wydawnictw Szkolnych}, year = {1964}, language = {Polish}, url = {https://katalog.ub.uni-leipzig.de/Record/0-1180764005} }