The sixth article's going through (3)
I believe the answer is:
'going through' is the definition.
(via means through)
'the sixth article's' is the wordplay.
'the sixth' becomes 'vi' (Roman numerals).
'article' becomes 'a' (the indefinite article in English).
(Other definitions for via that I've seen before include "Passing through", "A Roman way", "By way of - in Latin", "By means of", "Roman road".)