Chi-dao nguyen-bao in Vietnamese.
- Novak: #109b
dao wrongly read as thong
- Thierry: #1120
Brass. D = 23 mm. W = 1.61 g
Imitation of the Chinese cash coin Zhi-dao yuan-bao (995-996 AD), Emperor Tai Zong, Northern Song Dynasty.
Special calligraphy of the dao.
- YNLSHB: p.472, coin #7.
- Novak, John A. A working Aid for collectors of Annamese coins. Longview, Wash., USA, 1967.
- Thierry, François, Catalogue des monnaies vietnamiennes, Bibliothèque Nationale de France, Paris 1987. In French.
- Tang Guo Yen, Chang Shi Chuan Yuenan
lishi huobi (in Vietnamese Lich suu dong tien
Vietnam - The Vietnamese historical currency), 1993,
published by Yunnan and Guangxi Numismatic Society, in Chinese.