Legal aid sources that provide (5)

I believe the answer is:

layon

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

'legal aid sources that' is the wordplay.
'sources' indicates taking the first letters.
'that' becomes 'yon' (archaic term meaning 'that').
The first letters of 'legal aid' is 'la'.
'la'+'yon'='LAYON'

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I've seen this clue in The Daily Express.

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