CREATE TABLE table_18602462_21 (final__bronze_medal_match VARCHAR, event VARCHAR)

When mixed quad singles is the event what is the final/bronze medal match?
SELECT final__bronze_medal_match FROM table_18602462_21 WHERE event = "Mixed Quad Singles"
SELECT "final__bronze_medal_match" FROM "table_18602462_21" WHERE "Mixed Quad Singles" = "event"