UPDATE: I've noticed the CD label is "051013_1832".
This is a standard Italian date (05/10/2013 18:32; October 5, 2013 6:32 PM).
I believe whoever has written that disk has forgotten to set a label, so the burning program has used 051013_1832 as default. This makes sense.
Nero InfoTool is no help. Under "Disk" tab, it shows "Date: n/a".
This makes sense too, because the disk is not finalized. I think such a date would be set by finalizing the disk.