Lien, N. T. H., V. X. Hoa, V. T. T. Duong, N. V. Tinh, and T. H. Nhung. “Synthesis and Optical Properties of Colloidal Gold Nanoparticles for Biomedical Applications”. Communications in Physics, vol. 21, no. 1, Mar. 2011, p. 63, doi:10.15625/0868-3166/21/1/96.