Ngô Sĩ Liên et al., Đại Việt Sử Ký Toàn Thư"An Dương Vương" quote: "王於是築城于越裳,廣千丈,盤旋如螺形故號螺城。" tr: "The King then built a citadel at Việt Thường, one-thousand-zhàng wide, whirling and swirling like the shape of a snail. Therefore, it was called Snail Citadel (Loa Thành)."