As for the rest of the acts of Jotham, along with all his wars and his ways, they are indeed written in the Book of the Kings of Israel and Judah.
Jewish Publication Society of America Version (JPS1917) - 2 Chronicles 27:7 >Now the rest of the acts of Jotham, and all his wars, and his ways, behold, they are written in the book of the kings of Israel and Judah.