VS Pless, Z Qian - IEEE Transactions on Information Theory, 1996 - ieeexplore.ieee.org
… Theorem 2: Suppose C is a Z4-cycIic code of odd length n. Then there are unique, monic
polynomials f, g, and h such that C = (fh.2fg). where fgh = 2' - 1, and IC1 = 4deRg2degh. …