Unless you can demonstrate to me that every Old Testament reference in the New Testament is prefaced by "It is written" it sounds like busy work. Unless you have actually read the Deuterocanonicals (Tobit, Judith, Wisdom, Sirach (or Ecclesiasticus), Baruch, 1 Maccabees, and 2 Maccabees) and I have met very few Protestants who have, you would have to take my word for it or do your own Google searches.
Paul cited a Cretan when he wrote, “One of the Cretans, a prophet of their own, said, “Cretans are always liars, evil beasts, lazy gluttons.”
But was he saying the Cretan was a prophet of God, and his saying inspired? Not hardly.
There are lists that try to show that a phrase found in the NT draws from the Apocrypha, yet nowhere does Jesus or an Apostle use a writing from the Apocrypha for authority.
“44Then he said to them, “These are my words that I spoke to you while I was still with you, that everything written about me in the Law of Moses and the Prophets and the Psalms must be fulfilled.” 45Then he opened their minds to understand the Scriptures, 46and said to them, “Thus it is written...”
See this link for the times that “It is written” can be found - not all 120 references are applicable, but most are:
http://www.blueletterbible.org/search/translationResults.cfm?Criteria=written&t=ESV&csr=9&sf=5
You won’t find the Apocrypha cited.
BTW - what were the Deutercanonicals called prior to 1566?