ΚΑΤΕΧΩΡΗΘΗ ΗΜ. ΔΑΠ ...

13:52 Feb 28, 2010 

Thank you, Philip and Anna. I've just realised my mistake: these are αποδείξεις - receipts, of course, not invoices. Not that this invalidates your comments!
In fact, they're set out exactly like invoices. Perhaps they serve both purposes (invoice, receipt) at once.

There are some τιμολόγια later in the same set of documents.

13:01 Feb 28, 2010 

You are right, but to be accurate: Δελτίο Αποδείξεως Πληρωμής

12:21 Feb 28, 2010 

I think you're right, Dylan. It means the money has been paid (deposited) and has a cross reference to the receipt number and date of payment. (Good to see I'm not the only one working on Sunday afternoon :-)