https://digital.katalog.queersearch.org/s/katalog/item/38686, “Vorwiegend homosexuell: Aufsätze, Kommentare, Reden”, https://digital.katalog.queersearch.org/s/katalog/item/49268, QueerSearch, accessed 28. April 2025, https://digital.katalog.queersearch.org/s/katalog/item/28457