Source
Source: Johannes Glauburg and Johannes Völker. Siege of the city of
Frankfurt am Main, 1552, drawing (ca. 1555). Map Department, Berlin
State Library.
bpk-Bildagentur, image number 00006140. For rights
inquiries, please contact Art Resource at requests@artres.com (North
America) or bpk-Bildagentur at kontakt@bpk-bildagentur.de (for all other
countries).