Das, B. B., and R. G. Rao. “Sol-Gel Synthesis, Magnetic and Optical Properties of Co2+:Nd3+::2:1 Molar Ratio Doped in SiO2”. JOURNAL OF ADVANCES IN CHEMISTRY, vol. 11, no. 3, Apr. 2015, pp. 3367-74, doi:10.24297/jac.v11i3.864.