Leopold Kronecker wrote, "All results of the profoundest mathematical investigation must ultimately be expressible in the simple form of properties of integers." It is perhaps this feeling that made him say, "God made the integers, all the rest is work of humanity." Elementary number theory is related to the properties of the natural numbers 1, 2, 3, ..n. In the course of studying these properties it become requisite to take into account the ring of integers Z and then the field of rational numbers Q. The first systemic investigation of integers lying in an algebraic number field not...