To celebrate the opening of the exhibition “Hirschfeld-Fundstücke” on 6 December 2011, the Director General of the Central and State Library of Berlin Prof. Dr. Claudia Lux gave a copy of the book „Mein System“ by Gustav Jäger to the Magnus Hirschfeld Society on permanent loan. The book originates from the library of the Institute for Sexual Research, which was plundered by the Nazis. After 1945 it found its way into the Berlin City Library. Now the book has been discovered in the library’s own collection while researching objects looted by the Nazis.