Nguyen, V., A. Vu, and H. Ha. “Improvement in Conductivity and Thermal Stability of Polystyrene With Two-Step Reduced Graphene Oxide Based Nanocomposite Graphene /Polystyrene”. Science and Technology Development Journal, Vol. 17, no. 2, June 2014, pp. 90-99, doi:https://doi.org/10.32508/stdj.v17i2.1318.