Know they're upset by daily (3,3,4,5)

I believe the answer is:

the new york times

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'daily' is the definition.
Both the answer and definition are singular nouns.
Perhaps you can see a link between them that I don't see?

'know they're upset by' is the wordplay.
'upset' is an anagram indicator.
'by' becomes 'times' ('times' can mean multiplied by).
'know'+'theyre'='knowtheyre'
'knowtheyre' anagrammed gives 'thenewyork'.
'thenewyork'+'times'='THE NEW YORK TIMES'

Can you help me to learn more?

I've seen this clue in The Telegraph.

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