I have been confused by the use of the definite article or zero article before o-phrases. Take the following example, why zero article instead of the definite article is used before "Aspects" (As some of the grammar books tell us that the definite article should be used before of-phrases, but in here the zero article is used instead).
"Aspects of
the Irish constitution and its implementation are clearly oppressive as well as offensive to other minorities beside the Protestant one. "
Could you elaborate further on the use of the defintie article or zero article before of-phrases and give some examples of them please

?
(BTW, could you provide any links or books for my reference in this respect.)
Thank you very much and have a nice day.
Albertino