The QR code listed on your REF spheres are direct web-links to the DAKKS Cert from SAPHIRWERK.  If you scan the QR code with your phone (it is difficult as they are quite small), the link is a download link for the PDF of the DAKKS Cert

I was also told that there is a cost for a calibration certificate if we have to request one and that there may be some reference spheres in stock without QR codes.