Wu, Q., Qiang, T. C., Zeng, G., Zhang, H., Huang, Y., & Wang, Y. (2017). Sustainable and renewable energy from biomass wastes in palm oil industry: A case study in Malaysia. International Journal of Hydrogen Energy, 42(37), 23871-23877. https://doi.org/10.1016/j.ijhydene.2017.03.147