"Our Man in Havana" author (6)
I believe the answer is:
greene
'our man in havana author' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for greene that I've seen before include "Graham -, English author (Brighton Rock)" , "Graham --, British author" , "Graham --, Eng. author" , "See 13" , "The Quiet American author" .)