You seem to be attempting to access an item that has been removed from the repository.
There is a later version of the item you are trying to access:
Metzig, Robert and Schättler, Birgit and Younis, Marwan and Stangl, Martin (2006) TerraSAR-X System: Ground Segment - Space Segment Integration, Technical Verification and Validation Plan. Project Report. TX-PD-PL-0001, 86 S.