CREATE TABLE table_37347 ("Date" CLOB, "Opponent" CLOB, "Score" CLOB, "Loss" CLOB, "Attendance" FLOAT, "Record" CLOB)

What day is their record 13-15?
SELECT "Date" FROM table_37347 WHERE "Record" = '13-15'
SELECT "Date" FROM "table_37347" WHERE "Record" = '13-15'