https://digital.katalog.queersearch.org/s/katalog/item/47336, “Genie und Charakter: Sammlung männlicher Bildnisse”, https://digital.katalog.queersearch.org/s/katalog/item/49745, QueerSearch, accessed 30. April 2025, https://digital.katalog.queersearch.org/s/katalog/item/26261