Thai, T. H., Hien, N. T., Minh, D. T. and The, P. V. (2012) “The Chemical composition of leaf oil of Cupressus tonkinensis Silba. in Huu Lien, Lang Son province”, Academia Journal of Biology, 31(1), pp. 74–76. doi: 10.15625/0866-7160/v31n1.803.