M.S. Nurhaziqah, A., et al. “Microstructure And Electrical Study Of Biopolymer Based On Methylcellulose For Solar Cells”. International Journal of Engineering & Technology, vol. 7, no. 4.38, Dec. 2018, pp. 1466-9, https://doi.org/10.14419/ijet.v7i4.38.27902.