The Sun is one such publication! (9)
I believe the answer is:
newspaper
'publication' is the definition.
(I've seen this before)
'the sun is one' is the wordplay.
I cannot quite see how this works, but
'sun' could be 's' (abbreviation) and 's' is present in the answer.
'one' could be 'er' (I've seen this in other clues) and 'er' is found within the answer.
This may be the basis of clue (or it may be nonsense).
'such' acts as a link.
Can you help me to learn more?
(Other definitions for newspaper that I've seen before include "Publication on folded sheets" , "printed edition" , "Broadsheet, e.g." , "part of the media" , "Journal" .)