Please note when preparing the print file that the front of the voucher will be printed in full colour (CMYK) and the back will be in black & white. Please send your voucher as a PRINT-PDF/X-3 file to Dolde Werbeagentur GmbH,, the agency responsible for producing the voucher booklet. Hotline for technical queries or assistance in preparing the print file: +49(0) 711/13466-35,