N.Y. Est. Powers & Trusts Law § 10-9.1

§ 10-9.1 Revocability of a power of appointment\n (a) A power of appointment is irrevocable unless the donor reserves\nthe right to revoke it.\n (b) An exercise of power of appointment is irrevocable whenever:\n (1) The donor of a special power manifests his intention that its\nexercise be irrevocable, or\n (2) The donee does not manifest in the instrument exercising the power\nhis intention to reserve a power of revocation.\n (c) If the donee in exercising a power reserves a power to revoke the\nappointment, but does not expressly reserve a power to reappoint, upon\nthe exercise of the power of revocation, the donee can reappoint.\n (d) An instrument exercising a power of appointment is affected by\nfraud in the same manner as a deed or will, executed by an owner or by a\ntrustee of property.\n