Many ways
Usually it is related with serial number and prefix, sometimes printer label is separate from serial number and prefix, sometimes it is written specifically sometimes not, sometimes it is related with paper microfibers and so on.
Usually I visit respective National Bank's website to check these details.
In your case it should be related with serial numbers. If you cannot find info online you just ask someone working in a bank there. I worked in German banks for long time so I can only tell for German stuff