O.Thetford, P.Gray German Aircraft of the First World War (Putnam)

Germania Type C
   This aircraft, designated Type K.D.D. (Kampf Doppeldecker) by the manufacturers, was little more than a B I fitted with the more powerful 150 h.p. Benz Bz III engine and an elevated gun-ring in the rear cockpit to carry a Parabellum machine-gun. Only one built.

M.Dusing Germania Flugzeugwerke and its Aircraft (A Centennial Perspective on Great War Airplanes 41)

Germania KDD Combat Biplane
  
   The KDD (Kampfdoppeldecker = combat biplane) was designed in 1916 as an armed C-type aeroplane. The aircraft was powered by a 150 hp Benz Bz III engine. The basic construction of this aircraft equipped with a wooden fuselage did not differ from the previous models.
   It is not known that this aircraft was ever presented to the Heeresverwaltung. Only the prototype was built and tested in flight.