https://digital.katalog.queersearch.org/s/katalog/item/64624, https://digital.katalog.queersearch.org/s/katalog/item/64627, and https://digital.katalog.queersearch.org/s/katalog/item/65889, “Comparisons Among Heterosexual, Bisexual, and Homosexual Male Sado-Masochists”, QueerSearch, accessed 2. Juli 2025, https://digital.katalog.queersearch.org/s/katalog/item/60892