Lewin, G., & Felber, R. (1969). Historians of the GDR and the Problem of the "Mixed Formation": Contribution to the discussion "Pre- and Protohistory and the Problem of Historical Periodization". EAZ – Ethnographisch-Archaeologische Zeitschrift, 10(3), 369–386. https://doi.org/10.54799/SAES7337