Third Book of Kings (Author Compiled by Isaias and Jeremias from records of Nathan, Gad, Addo, Ahias, Jehu and others.)
2:33et revertetur sanguis illorum in caput Ioab et in caput seminis eius in sempiternum David autem et semini eius et domui et throno illius sit pax usque in aeternum a Domino
Original from The Bible Foundation - bf.org. They claim public domain status for their original text.