Crossword Genius

Swamp roster in bumf... (3,4)

Ross

I believe the answer is:

bog roll

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

'swamp roster' is the wordplay.
'swamp' becomes 'bog' (both can mean a wet or marshy area).
'roster' becomes 'roll' (synonyms).
'bog'+'roll'='BOG ROLL'

'in' acts as a link.

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I've seen this clue in the Sydney Morning Herald.
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