Sides wrangling over author's issue (8)
I believe the answer is:
dispense
'issue' is the definition.
(I've seen this before)
'sides wrangling over author's' is the wordplay.
'wrangling' is an anagram indicator (wrangle can mean to round up and organise).
'over' indicates putting letters inside.
'author' becomes 'pen' (to pen something is to author it).
'sides' is an anagram of 'disse'.
'disse' going around 'pen' is 'DISPENSE'.
(Other definitions for dispense that I've seen before include "Enforce (justice)" , "Deal out or distribute" , "Execute" , "Supply (prescription)" , "Do without - give to others" .)