T. Nguyễn Thu, G. Hoàng Thị Hương, T. Nguyễn Thị Bích, and T. Lê Nho, “Study on the effects of lignin extracted from Bai Bang paper mill waste on the physico-mechanical properties of 60/70 penetration grade bitumen”, vn, vol. 77, no. 8, pp. 1069-1083, 1791997200.