2 Kings 8:23
And the rest of the acts of Joram, and all that he did, are they not written in the book of the chronicles of the kings of Judah? And the rest of the acts of Joram, and all that he did, are they not written in the book of the chronicles of the kings of Judah?
The opening twelve chapters of 2 Kings belong to Elijah and Elisha, embracing the closing days of Elijah and his translation and the noble, godly life of Elisha through whom God performed notable miracles and reproved and instructed backsliding Israel. Within that larger portion this statement stands in the record that traces the house of Ahab to its extinction. That extinction reaches into Judah because Athaliah, the wicked daughter of Ahab, carries into Judah the spirit of Jezebel her mother.
The statement falls in 2 Kings 6–8, within the books of Kings, which recount the history of Israel more fully than that of Judah, while Chronicles recounts the history of Judah more fully than that of Israel. It declares that the remainder of the acts of Joram and all that he did are written in the book of the chronicles of the kings of Judah. That written historical record is thereby identified as the place where fuller details of his reign may be found.