I agree with Hanne that this looks like a type, and this seems to be borne out by the fact that the same type of document come up from searches on both spellings. This was a new one for me. But from what I can see, it seems to be some kind of receipt or acknowledgement note. E.g. "Liste P04 - avkvittering ved kontroll av søknader mot endringer i folkeregisteret - vil bli gjort tilgjengelig på Ekstranett og tas ut etter kopiering, jf. tidsplan."(http://www.husbanken.no/Home/Venstremeny/Bostotte/Husbankens... ). Also, I see that the few hits I do get refer to them being received from either Skattedirektoratat or Folkeregisteret, which support my hunch. The link below has "avkvittering" listed under "utskrifter" which also suggests some kind of document.

I think this is appropriate in this context.