 Complete the following phrase:  The diocese of Gumal was located in the Mosul district of northern Iraq, not far from the celebrated Jacobite monastery of Mar Mattai. According to Bar Hebraeus, Gumal was a large town in the country of Marga, to the northeast of Mount Alpap. The town is probably connected with the district of Tel Gomel in Greek, Gaugamela, which gave its name to Alexander the Greats 