S.D. Codified Laws § 29A-2-506

A written will is valid if executed in compliance with § 29A-2-502 or 29A-2-503 or if its execution complies with the law at the time of execution of the jurisdiction where the will is executed, or of the law of the jurisdiction where at the time of execution or at the time of death the testator is domiciled, has a place of abode, or is a national.