Note 137
From Chapter 40 of the Decline & Fall

The description of Dara is amply and correctly given by Procopius, (Persic. l. i. c. 10, l. ii. c. 13. De Edific. l. ii. c. 1, 2, 3, l. iii. c. 5.) See the situation in D'Anville, (l'Euphrate et le Tigre, p. 53, 54, 55,) though he seems to double the interval between Dara and Nisibis.