Various papers written up on poetry (7)
I believe the answer is:
diverse
'various' is the definition.
('diverse' can be a synonym of 'various')
'papers written up on poetry' is the wordplay.
'papers' becomes 'id' (identification papers).
'written up' says the letters should be written in reverse.
'on' means one lot of letters go next to another.
'poetry' becomes 'verse' ('verse' can be a synonym of 'poetry'**).
'id' reversed gives 'di'.
'di'+'verse'='DIVERSE'
(Other definitions for diverse that I've seen before include "Several" , "Many and varied" , "Differing" , "Multifarious" , "Miscellaneous" .)