"Das haus in der Garibaldi Straße (The House on Garibaldi Street)". Der Spiegel (in German). 6 July 1975. Retrieved 28 August 2021. In this article there was just a hint to Zinn ("Eine hochstehende Persönlichkeit von großer Integrität" - a very important person of great integrity), whose name and role were not clearly revealed before the aforementioned 1997 Shpiro's introduction.
