https://digital.katalog.queersearch.org/s/katalog/item/37416, https://digital.katalog.queersearch.org/s/katalog/item/37383, and https://digital.katalog.queersearch.org/s/katalog/item/37501, “Die Freundin 1930 - Ausgabe 18”, QueerSearch, accessed 29. April 2025, https://digital.katalog.queersearch.org/s/katalog/item/3579