First Book of Paralipomenon (Author Compiled by Isaias and Esdras from records of Nathan, Gad, Addo, Ahias, Jehu and others.)
26:32fratresque eius robustioris aetatis duo milia septingenti principes familiarum praeposuit autem eos David rex Rubenitis et Gadditis et dimidio tribus Manasse in omne ministerium Dei et regis
Original from The Bible Foundation - bf.org. They claim public domain status for their original text.