N. Q. Vuong, K. Nakjoong, T. T. Phuong Thao, N. L. Tuan, and T. V. Sung, “Synthesis of new alkoxy substituted 4-piperidinobenzylidene malononitrile (PDCST) nonlinear optical chromophores”, VJChem, vol. 55, no. 2, p. 163, Apr. 2017.