Joshua 13:10

and all the cities of Sihon, king of the Amorites which reigned in Heshbon, even unto the borders of the children of Ammon;

Numbers 21:24-26

And Israel smote him with the edge of the sword and conquered his land, from Arnon unto Jabbok: even unto the children of Ammon. For the borders of the children of Ammon are strong.

Treasury of Scripture Knowledge did not add