Hoque, M. A., and Y. Kawakami. “Synthesis of Polysilsesquioxanes With Double-Decker Silsesquioxane Repeating Units”. Journal of Scientific Research 8, no. 2 (May 1, 2016): 217–227. Accessed March 20, 2023. https://www.banglajol.info/index.php/JSR/article/view/26791.