Here is a sample authorization letter for authentication of documents.
Subject: Authorization Letter to Authenticate Documents on My Behalf
I, [Your Name], give [Name of Entrusted Person] the authority to sign the following documents on my behalf.
They will have the authority to sign [mention documents]. They will not have the authority to sign [mention excluded documents]. Their authority to sign on my behalf will be valid from [Date] to [Date].
I have enclosed my identification proof with my signature below, as well as verification for the entrusted authority.
These are the details of the authorized individual.
Authorized Person: [Name of Entrusted Person]
Identity Document Number:
Signature: [Signature of Entrusted Person]
Start Date of Action:
End Date of Action:
[Signatures of all concerned parties]