Have you tried the South Dakota Birth Record Search at
http://www.state.sd.us/doh/vitalrec/birthrecords/index.cfmI found this.
Birth Information for NORA OTHILIE OLSEN
(State File Number: 774192)
File Date: 10/02/1957
Sex: Female
Birth Date: 12/06/1891
City/County: YANKTONCO
Mother's Name: ANNETTE ANDERSON LUND
Father's Name: CHRISTIAN OLSEN
Ray Justus
Chandler, AZ