TRAKARNPRUK, W., and A. SIRIKULKAJORN. “Iron Complexes for Oligomerization of Hexene”. Journal of Metals, Materials and Minerals, vol. 13, no. 2, Aug. 2022, pp. 71-78, https://www.jmmm.material.chula.ac.th/index.php/jmmm/article/view/1468.