Classify authors for printing machines (11)

I believe the answer is:

typewriters

'printing machines' is the definition.
(typewriter is a kind of printing machine)

'classify authors' is the wordplay.
'classify' becomes 'type' (I've seen this in another clue).
'authors' becomes 'writers' ('writer' can be a synonym of 'author').
'type'+'writers'='TYPEWRITERS'

'for' acts as a link.

(Another definition for typewriters that I've seen is " office equipment".)

I've seen this clue in The Irish News.

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