A Diophantine Definition of Rational Integers over Some Rings of Algebraic Numbers

The author considers the rings of algebraic numbers integral at all but finitely many primes in the number fields, where it has been previously shown that Hubert's Tenth Problem is undecidable in the rings of algebraic integers, and proves that the problem is still undecidable in the bigger rings by constructing a diophantine definition of rational integers there.