2 Chronicles (Author Compiled by Isaiah and Ezra from records of Nathan, Gad, Iddo, Ahijah, Jehu and others.)
18:29And the king of Israel said unto Jehoshaphat, I will disguise myself, and will go to the battle; but put thou on thy robes. So the king of Israel disguised himself; and they went to the battle.
Original from The Bible Foundation - bf.org. They claim public domain status for their original text.