who is the the womens singles with mixed doubles being bernd frohnwieser hilde themel and year being smaller than 1959.0
CREATE TABLE "past_winners" (
  "year" real,
  "mens_singles" text,
  "womens_singles" text,
  "mens_doubles" text,
  "womens_doubles" text,
  "mixed_doubles" text
);
SELECT "womens_singles" FROM "past_winners" WHERE "mixed_doubles"='Bernd Frohnwieser Hilde Themel' AND "year"<1959.0;