I. B. Karki, S. Chatterjee, J. J. Nakarmi, D. Sinha, D. Goswami, and P. K. Mandal, “Photovoltaic Characterization of Dye-sensitized Solar Cells with Natural Dyes using Synthesized ZnO nanostructures”, J. Nepal Chem. Soc., vol. 30, pp. 56–61, Dec. 2013.