And as a follow-on to that:
There was never any such aircraft as the Halberstadt CL-I because the company & army both were apparently following the numerical sequence from the earlier types produced by the same company. To add t the confusion, there were a couple of different Halberstadt C-I aircraft: an experimental C-I, and then a licensed-built copy of the DFW C-V (originally known also as the Halberstadt, then the designation was changed to DFW C-V (Halb)). Then the Halberstädter Fleuzug-Werke built their CL-II. They also did produce a "regular" C-III, and followed up their CL-II with a CL-IV, also fairly widely accepted by the Luftstreitkräfte.

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