Lạng Sơn province (English Wikipedia)

Merriam-Webster, Inc (1997). Merriam-Webster's geographical dictionary. Merriam-Webster. p. 628. ISBN 0-87779-546-0.
Colet, John; Joshua Eliot (2002). Vietnam handbook. Footprint Travel Guides. pp. 144–146. ISBN 1-903471-31-1. Retrieved 2010-08-26.
Ray, Nick; Peter Dragicevich; Regis St. Louis (2007). Vietnam. Lonely Planet. pp. 153–154. ISBN 978-1-74104-306-8. Retrieved 2010-08-26.

asiaforestnetwork.org

"Filed Guide to Vietnam:Limestone Forest: Beyond Stunning Beauty" (PDF). Asia Forest Network. pp. 5, 16. Archived from the original (PDF) on 2008-08-28. Retrieved 2010-08-26.

Boobbyer, Claire (2008). Footprint Vietnam. Footprint Travel Guides. pp. 136–139. ISBN 978-1-906098-13-1. Retrieved 2010-08-26.
Pietrusewsky, Michael; Toomay Douglas, Michele (2002). "Ban Chiang, a prehistoric village site in northeast Thailand: the human skeletal remains". Ban Chiang, a Prehistoric Village Site in Northeast Thailand. Vol. 1. UPenn Museum of Archaeology. p. 224. ISBN 0-924171-92-8.
Mother Jones Magazine. Mother Jones Magazine. November 1983. p. 22. Retrieved 2010-08-26.
Discovery Channel (Firm) (2003). Vietnam. Langenscheidt Publishing Group. p. 209. ISBN 981-234-984-7. Retrieved 2010-08-26.
Guide to Vietnam. Bradt Travel Guides. 1998. pp. 40, 46. ISBN 1-898323-67-4. Retrieved 2010-08-26.
Peter, K.V. (2004). Handbook of herbs and spices. Vol. 2. Woodhead Publishing. ISBN 1-85573-721-3.

General Statistics Office of Vietnam (2019). "Completed Results of the 2019 Viet Nam Population and Housing Census" (PDF). Statistical Publishing House (Vietnam). ISBN 978-604-75-1532-5.
"Number of cooperatives in 2008 by kind of activity and by province: Agriculture, Forestry and Fishery". Population and Employment :General Statistics Office of the Government of Vietnam. Archived from the original on 2009-11-13. Retrieved 2010-06-23.
"Agriculture, Forestry and Fishery: Number of cooperatives by province". Population and Employment :General Statistics Office of the Government of Vietnam. Archived from the original on 2009-11-13. Retrieved 2010-06-23.
"Agriculture, Forestry and Fishery: Number of farms by province". Population and Employment :General Statistics Office of the Government of Vietnam. Archived from the original on 2009-11-13. Retrieved 2010-06-23.
"Agriculture, Forestry and Fishery :Output value of agriculture at constant 1994 prices". Population and Employment :General Statistics Office of the Government of Vietnam. Archived from the original on 2009-11-13. Retrieved 2010-06-23.

Biểu số 4.1: Hiện trạng sử dụng đất vùng Trung du và miền núi phía Bắc năm 2022 [Table 4.1: Current land use status in the Northern Midlands and Mountains in 2022] (PDF) (Decision 3048/QĐ-BTNMT) (in Vietnamese). Ministry of Natural Resources and Environment (Vietnam). 18 October 2023. – the data in the report are in hectares, rounded to integers

"Annuaire Statistique du Vietnam" (PDF) (in French). Archived from the original (PDF) on 2021-05-10. Retrieved 2023-08-14.

"Vichy Indo-China vs Japan, 1940". Stone & Stone Second World War Books. Retrieved 2010-08-26.

"Annuaire Statistique du Vietnam" (PDF) (in French). Archived from the original (PDF) on 2021-05-10. Retrieved 2023-08-14.
"Filed Guide to Vietnam:Limestone Forest: Beyond Stunning Beauty" (PDF). Asia Forest Network. pp. 5, 16. Archived from the original (PDF) on 2008-08-28. Retrieved 2010-08-26.
"Number of cooperatives in 2008 by kind of activity and by province: Agriculture, Forestry and Fishery". Population and Employment :General Statistics Office of the Government of Vietnam. Archived from the original on 2009-11-13. Retrieved 2010-06-23.
"Agriculture, Forestry and Fishery: Number of cooperatives by province". Population and Employment :General Statistics Office of the Government of Vietnam. Archived from the original on 2009-11-13. Retrieved 2010-06-23.
"Agriculture, Forestry and Fishery: Number of farms by province". Population and Employment :General Statistics Office of the Government of Vietnam. Archived from the original on 2009-11-13. Retrieved 2010-06-23.
"Agriculture, Forestry and Fishery :Output value of agriculture at constant 1994 prices". Population and Employment :General Statistics Office of the Government of Vietnam. Archived from the original on 2009-11-13. Retrieved 2010-06-23.