Herr, Larry. The Scripts of the Ancient Northwest Semitic Seals, Harvard Semitic Monographs 18, Missoula: Scholars Press, 1978.
This book is a revision of the author’s doctoral dissertation completed under Cross. Herr attempts to organize the hundreds of inscribed seals from the late Iron Age based on script type in order to differentiate national script traditions and provide a framework for paleographic dating. The seals are divided into Aramaic, Ammonite, Hebrew, Moabite, Edomite, and Phoenician. He concludes that in the 8th century the northern script (Aramaic/Ammonite) has clearly differentiated from the southern (Israel, Judah, Edom and Moab). After c.730 the Ammonite script diverged from Aramaic and the trans-Jordan scripts begin to show Aramaic elements. However, this development never occurred in Judah where the Hebrew script developed its own tradition apart from the Moabite/Edomite scripts. With the Babylonian invasion the Hebrew script was replaced by the Judean Provincial Aramaic script during the mid 6th to early 5th centuries.