Austrian U-12o or U-12S

During the thirties there were build the Udet U-12 under licence in Austria
Major Hammerle designed an improve version the U-12o also U-12S, with steel-tube fuselage and some other improvenments.
Who can help me with the following details/materials:
1. Drawings;
2. Drawings/pictures/etc which gives an impression of the fuselage construction;
3. Dimensions;
4. Other interresting details/materials/colors of this version of the U-12.

Thanks
Jan