World War I - Kaiserliche Marine - Uboat.net. Penwith District Council. Boat Types. Penzance: Penwith District Council. 2009 [2009-03-04]. (原始内容存档于2007-05-27)
World War I. Uboat.net. Retrieved 2009-03-30. Penwith District Council. Boat Types. Penzance: Penwith District Council. 2009 [2009-03-04]. (原始内容存档于2007-05-27)