Nottelmann, pp. 184–188, 193. Nottelmann, Dirk (2023). Wright, Christopher C. (ed.). "From "Wooden Walls" to "New-Testament Ships": The Development of the German Armored Cruiser 1854–1918, Part IIIb: "Armor—Light Version"". Warship International. LX (3): 184–228. ISSN0043-0374.
Nottelmann, p. 221. Nottelmann, Dirk (2023). Wright, Christopher C. (ed.). "From "Wooden Walls" to "New-Testament Ships": The Development of the German Armored Cruiser 1854–1918, Part IIIb: "Armor—Light Version"". Warship International. LX (3): 184–228. ISSN0043-0374.
Nottelmann, p. 222. Nottelmann, Dirk (2023). Wright, Christopher C. (ed.). "From "Wooden Walls" to "New-Testament Ships": The Development of the German Armored Cruiser 1854–1918, Part IIIb: "Armor—Light Version"". Warship International. LX (3): 184–228. ISSN0043-0374.