https://digital.katalog.queersearch.org/s/katalog/item/63884, “Die Rassenhygienische Bewegung in Deutschland, 1904-1933”, https://digital.katalog.queersearch.org/s/katalog/item/49445, QueerSearch, accessed 29. April 2025, https://digital.katalog.queersearch.org/s/katalog/item/55704