S.D. Codified Laws § 29A-2-704

If a governing instrument creating a power of appointment expressly requires that the power be exercised by a reference, an express reference, or a specific reference, to the power or its source, it is presumed that the donor's intention, in requiring that the donee exercise the power by making reference to the particular power or to the creating instrument, was to prevent an inadvertent exercise of the power.