Very small volume kept by the secretary (6-4)

I believe the answer is:

minute-book

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'kept by the secretary' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'very small volume' is the wordplay.
'very small' becomes 'minute' (minute can mean tiny).
'volume' becomes 'book' (book is a kind of volume).
'minute'+'book'='MINUTE-BOOK'

Can you help me to learn more?

I've seen this clue in The Irish Independent.

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