A note on Itoh (e)-valuation rings of an ideal

(4) If the Rees integers of I are all equal to e, then V⁎=W[θe] is a simple free integral extension domain of W, QV⁎=N⁎=u1eV⁎, and [V⁎:W]=e=[(V⁎/N⁎):(W/Q)].