CREATE TABLE table_5648 ("Outcome" TEXT, "Date" TEXT, "Tournament" TEXT, "Surface" TEXT, "Partner" TEXT, "Opponents" TEXT, "Score" TEXT)

Who is the partner of the tournament on 6 July 1987?
SELECT "Partner" FROM table_5648 WHERE "Date" = '6 july 1987'
SELECT "Partner" FROM "table_5648" WHERE "Date" = '6 july 1987'