CREATE TABLE table_62284 ("Round" FLOAT, "Race" TEXT, "Circuit" TEXT, "Date" TEXT, "Event" TEXT, "Winning driver" TEXT, "Winning team" TEXT)

What is the date that Fabrizio Giovanardi Christian Abt won?
SELECT "Date" FROM table_62284 WHERE "Winning driver" = 'fabrizio giovanardi christian abt'
SELECT "Date" FROM "table_62284" WHERE "Winning driver" = 'fabrizio giovanardi christian abt'