Book at that time peaked — a novel (3,5,3)

I believe the answer is:

the naked ape

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'book' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'that time peaked a novel' is the wordplay.
'that time' becomes 'then' (I've seen this in another clue).
'novel' is an anagram indicator (letters in a new or novel order).
'peaked'+'a'='peakeda'
'peakeda' with letters rearranged gives 'akedape'.
'then'+'akedape'='THE NAKED APE'

'at' is the link.

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I've seen this clue in The Independent.

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