You might check Michael Dobson's web site "Descendants of Robert Royce of New London, Connecticut". This could be his Frank Wilbur ROYCE, 20 Apr 1858 - 20 May 1943. Frank Wilbur ROYCE's father died in South Dakota. Or you could check for a South Dakota record of Frank's death 20 May 1943 and hope that might lead to a corresponding obituary.