1. Lo, H.S., Ko, W.C., Chen, W.C., Hsue, H.H., and Wu, H. (1999). Flora Reipublicae Popularis Sinicae: Tomus 71(1): Angiospermae Dictotyledoneae, Rubiaceae (1), Science Press.
2. Mojiol, A.R., Lintangah, W., Maid, M., and Julius, K. (2018). Enzyklopädie der Holzgewächse: Handbuch und Atlas der Dendrologie, Wiley Online Library.
3. Yacob, N., Mohamed, M., and Megat Hanafiah, M. (2016). Regional Conference on Science, Technology and Social Sciences (RCSTSS 2014), Springer.
4. Effect of radial growth rate on wood properties of Neolamarckia cadamba;Pertiwi;J. Trop. For. Sci.,2017
5. Wasli, M.E., Sani, H., Ahmad, F.B., Mohamad, S., Teen, L.P., Soon, L.K., and Sidi, M. (2012). Sustaining Tropical Natural Resources Through Innovations, Technologies and Practices. Proceedings of the 4th Regional Conference on Natural Resources in the Tropics, Kota Samarahan, Malaysia, 19–20 September 2012, Faculty of Resource Science and Technology.