Tài liệu tham khảo WikiPedia: Vĩnh_Trại //tools.wmflabs.org/geohack/geohack.php?language=v... http://vanphong.langson.gov.vn/sites/vanphong.lang... http://mic.gov.vn/uploads/20100623/E124-2009%20(31... https://web.archive.org/web/20130324095035/http://...
