attestation (suomeksi)

todistus (s: such a confirmation or authentication)
vahvistus (s)
oikeaksi todistaminen (s)
todiste (s: something which bears witness, confirms or authenticates)
lausunto (s: providing an independent opinion, on published information of an organization, by accountants or auditors)
attestaatio (s: linguistics: appearance in records)
esiintyminen (s: linguistics: appearance in records)