An advertisement page in an old German book titled Universal Radsport-Karte, published around 1905 by Verlag von Theod. Thomas in Leipzig.
The book includes maps for bicycle tours in Saxony. Dürkopp was a producer of sewing machines, bicycles, motorcycles and cars, founded in 1867 in Bielefeld. The company still exists today under the name Dürkopp Adler.
I found it during the “museum night” in the geoscientific map collection by the University of Leipzig.