Tài liệu tham khảo WikiPedia: Trận_Opequon http://www.bibliobase.com/history/readerscomp/civw... http://www.cr.nps.gov/hps/abpp/battles/va119.htm http://www.civilwar.org/battlefields/third-winches... //tools.wmflabs.org/geohack/geohack.php?language=v...