A whale of a book (4-4)

I believe the answer is:

moby-dick

I believe this is a double definition.

'a whale' is the first definition.
(I've seen this before)

'a book' is the second definition.
(I've seen this before)

'of' acts as a link.

(Another definition for moby-dick that I've seen is " Book by Herman Melville".)

I've seen this clue in The Guardian.

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