1 Chronicles (Author Compiled by Isaiah and Ezra from records of Nathan, Gad, Iddo, Ahijah, Jehu and others.)
18:4And David took from him a thousand chariots, and seven thousand horsemen, and twenty thousand footmen: David also houghed all the chariot horses, but reserved of them an hundred chariots.
Original from The Bible Foundation - bf.org. They claim public domain status for their original text.