CREATE TABLE table_5573 ("Outcome" TEXT, "Date" TEXT, "Tournament" TEXT, "Surface" TEXT, "Partner" TEXT, "Opponents in Final" TEXT, "Score in Final" TEXT)

Which Partner has a Date of june 18, 1989?
SELECT "Partner" FROM table_5573 WHERE "Date" = 'june 18, 1989'
SELECT "Partner" FROM "table_5573" WHERE "Date" = 'june 18, 1989'