LALY, S., and GEETHA PARAMESWARAN. “Some Lanthanide Complexes of Semicarbazone and Thiosemicarbazone Derived from Fluorenone”. Asian Journal of Chemistry, vol. 6, no. 2, June 2010, pp. 389-92, https://asianpubs.org/index.php/ajchem/article/view/24558.