What is the surface of the match when the outcome was runner-up, and a Score of julia görges polona hercog?
CREATE TABLE "doubles_5_13" (
  "outcome" text,
  "date" text,
  "surface" text,
  "opponent" text,
  "score" text
);
SELECT "surface" FROM "doubles_5_13" WHERE "outcome"='runner-up' AND "score"='julia görges polona hercog';