Express found among European ship's papers (6)
I believe the answer is:
essays
'papers' is the definition.
(academic papers)
'express found among european ship's' is the wordplay.
'express' becomes 'say' (saying is a kind of expressing).
'found among' means one lot of letters goes inside another.
'european' becomes 'E' (abbreviation e.g. EU).
'ship' becomes 'SS' (prefix in ship names eg SS Great Britain).
'e'+'ss'='ess'
'say' inserted within 'ess' is 'ESSAYS'.
(Other definitions for essays that I've seen before include "Attempts - written compositions" , "Short pieces of writing as for homework" , "texts" , "Compostions and tracts" , "Makes attempt to do short pieces of writing" .)