CREATE TABLE table_16517 ("Team" TEXT, "Outgoing manager" TEXT, "Manner of departure" TEXT, "Date of vacancy" TEXT, "Replaced by" TEXT, "Date of appointment" TEXT)

What manner of departure is listed with an appointment date of 13 march 2008
SELECT "Manner of departure" FROM table_16517 WHERE "Date of appointment" = '13 March 2008'
SELECT "Manner of departure" FROM "table_16517" WHERE "Date of appointment" = '13 March 2008'