On what surface was the 26 August 2001 tournament played?
CREATE TABLE "doubles_runner_up_16" (
  "date" text,
  "tournament" text,
  "surface" text,
  "partner" text,
  "opponents_in_final" text,
  "score" text
);
SELECT "surface" FROM "doubles_runner_up_16" WHERE "date"='26 august 2001';