CREATE TABLE table_56712 ("Date" TEXT, "Visitor" TEXT, "Score" TEXT, "Home" TEXT, "Leading scorer" TEXT, "Attendance" FLOAT, "Record" TEXT)

Who was the visiting team on December 17?
SELECT "Visitor" FROM table_56712 WHERE "Date" = 'december 17'
SELECT "Visitor" FROM "table_56712" WHERE "Date" = 'december 17'