Ngo, T.L., Hölscher, D., 2013. The abundance of five rare tree species in forests on limestone hills of northern Vietnam. International Journal of Biodiversity and Conservation 5(11): 729-740.
Ngo The Long, Tran Thi Quyen, Phung Dinh Trung, 2008. The Initial Research on Reasons for the Broken Stem Phenomenon of Hybrid Acacia Trees at Ham Yen Station, Tuyen Quang Province. Vietnam Journal of Forest Science. No 02, 603-608.
Ngo The Long, 2009. Research on the Relationship between Measured Factors and Base Diameter, being the Scientific Basic for Accurately Determining Stem Volume and so Tracking down the Lost Volume of Acacia Trees in Ham Yen District, Tuyen Quang Province. Vietnam Journal of Forest Science. No 01, 541-545.