'Book' in the Bible

So all Israel were reckoned by genealogies; and, behold, they were written in the book of the kings of Israel and Judah, who were carried away to Babylon for their transgression.

Now the acts of David the king, first and last, behold, they are written in the book of Samuel the seer, and in the book of Nathan the prophet, and in the book of Gad the seer,