Signature of Paul Langen (1893–1945), opponent and victim of national socialism and headmaster of the catholic primary school in Holzlar near Bonn from 1931 to 1943.
Retrieved from a document signed by Langen as found in:Ahlborn, Lukas (September 2009). Verehrter, verkannter und fast vergessener Held? Der Bonner Hauptlehrer Paul Langen. (in German) (Free hardcopy on request) page 15. Retrieved on October 2011.
Paul Langen