CREATE TABLE table_37989 ("Date" CLOB, "Opponent" CLOB, "Site" CLOB, "Result" CLOB, "Attendance" CLOB)

What date was the Site michigan stadium ann arbor, mi?
SELECT "Date" FROM table_37989 WHERE "Site" = 'michigan stadium • ann arbor, mi'
SELECT "Date" FROM "table_37989" WHERE "Site" = 'michigan stadium • ann arbor, mi'