Delivery documentation variously bathetic and terrific (5,11)

I believe the answer is:

birth certificate

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'delivery documentation variously bathetic and terrific' is the definition.
I can't tell whether this definition defines the answer.

'variously bathetic and terrific' is the wordplay.
'variously' indicates anagramming the letters.
'and' says to put letters next to each other.
'bathetic' after 'terrific' is 'terrificbathetic'.
'terrificbathetic' is an anagram of 'BIRTH CERTIFICATE'.

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(Other definitions for birth certificate that I've seen before include "Evidence of age" , "Proof of age" , "Official ID document" .)

I've seen this clue in The Times.

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