Zhao, Wei, Mi Jai Lee, Hyung Tae Kim, Yoo Jin Kim, Jianghong Gong, and Ik Jin Kim. 2011. “Formation of Multi-Walled Carbon Nanotubes by Catalytic Chemical Vapour Deposition Using Zeolite Encapsulated Nanocrystalline Cobalt Oxides”. Asian Journal of Chemistry 23 (12):5457-60. https://asianpubs.org/index.php/ajchem/article/view/11165.