https://digital.katalog.queersearch.org/s/katalog/item/43666, “Contraception (Birth Control), its Theory, History and Practice. A Manual for the Medical and Legal Professions”, https://digital.katalog.queersearch.org/s/katalog/item/49908, QueerSearch, accessed 1. Mai 2025, https://digital.katalog.queersearch.org/s/katalog/item/26651