Uniqueness of Kerr space-time near null infinity

We reexpress the Kerr metric in standard Bondi-Sachs coordinates near null infinity I(+). Using the uniqueness result of the characteristic initial value problem, we prove the Kerr metric is the only asymptotically flat, stationary, axially symmetric, type-D solution of the vacuum Einstein equation. The Taylor series of Kerr space-time is expressed in terms of Bondi-Sachs coordinates, and the Newman-Penrose constants have been calculated.