John Gill Commentary 1 Kings 15:7

"And the rest of the acts of Abijam, and all that he did, are they not written in the book of the chronicles of the kings of Judah? And there was war between Abijam and Jeroboam." — 1 Kings 15:7 (ASV)

Now the rest of the acts of Abijam, and all that he did, are they not written in the book of the chronicles of the kings of Judah ? &c.] Which seem to be written by Iddo the prophet, see (2 Chronicles 13:22) ,

and there was war between Abijam and Jeroboam ; and a famous pitched battle between them we read of in (2 Chronicles 13:3 2 Chronicles 13:17) .