Songpanit, M., W. Mekprasart, and K. N. Ishihara. “Colorimetric Oxygen Indicator from Titanium Dioxide Nanocomposite by Mechanical Milling Process”. Thai Journal of Nanoscience and Nanotechnology, vol. 6, no. 1, June 2021, pp. 8-15, https://ph05.tci-thaijo.org/index.php/TJNN/article/view/73.