Note 284 — Chapter XVII · EVENTS FOLLOWING THE BATTLE OF CADESIYA—CAPTURE OF MEDAIN. A.H. XV., XVI. A.D. 636–7.
Reading edition
It is also called Nahr Shîr, and is described as beyond (i.e. to the east of) Sabât. In the earlier campaigns, this name of Nahr Shîr frequently occurs, as the point at which the pursuit of the victorious columns was stopped by the Persian outposts.