When playing on grass who was the opponents in a year greater than 1993, and playing with Jonas Björkman?
CREATE TABLE "grand_slam_men_s_doubles_finals_20_16_4" (
  "outcome" text,
  "year" real,
  "championship" text,
  "surface" text,
  "partner" text,
  "opponents" text,
  "score" text
);
SELECT "opponents" FROM "grand_slam_men_s_doubles_finals_20_16_4" WHERE "surface"='grass' AND "year">1993 AND "partner"='jonas björkman';