Second Book of Kings (Author Compiled by Isaias from records of Samuel, David, Nathan, and Gad.)
24:10percussit autem cor David eum postquam numeratus est populus et dixit David ad Dominum peccavi valde in hoc facto sed precor Domine ut transferas iniquitatem servi tui quia stulte egi nimis
Original from The Bible Foundation - bf.org. They claim public domain status for their original text.