https://digital.katalog.queersearch.org/s/katalog/item/42955, “Sex and the Weimar Republic: German Homosexual Emancipation and the Rise of the Nazis”, https://digital.katalog.queersearch.org/s/katalog/item/49312, QueerSearch, accessed 2. Mai 2025, https://digital.katalog.queersearch.org/s/katalog/item/25227