https://digital.katalog.queersearch.org/s/katalog/item/41208, “Anders als die Andern: Magnus Hirschfeld (1868-1935)”, https://digital.katalog.queersearch.org/s/katalog/item/50449, QueerSearch, accessed 29. April 2025, https://digital.katalog.queersearch.org/s/katalog/item/55423