When was the the ship launched ,that along with the Tripitz and the Lützow was a target for  Operation Source ?
Operation Source Operation Source was a series of attacks to neutralise the heavy German warships – "Tirpitz", "Scharnhorst" and "Lützow" – based in northern Norway, using X-class midget submarines.
USS Zeppelin (1914) USS "Zeppelin was a passenger liner launched in 1914 as SS "Zeppelin by Bremer Vulkan, Bremen-Vegesack, Germany, for Norddeutscher Lloyd (NDL). Due to the First World War she never entered NDL service. She had a career after the war first under White Star Line control, then briefly as the troop ship USS "Zeppelin, next as the Orient SN Co liner SS "Ormuz and finally back with NDL as SS "Dresden".