CREATE TABLE table_15138 ("Name" TEXT, "Circuit" TEXT, "Date" TEXT, "Winning driver" TEXT, "Winning constructor" TEXT, "Report" TEXT)

In the circuit of Madonie, what was the date that had the winning constructor Bugatti?
SELECT "Date" FROM table_15138 WHERE "Circuit" = 'madonie' AND "Winning constructor" = 'bugatti'
SELECT "Date" FROM "table_15138" WHERE "Circuit" = 'madonie' AND "Winning constructor" = 'bugatti'