Balani, Daya, et al. “Spectrophotometric Study of Doped Pr(III) Ion in Saturated Solutions of Carbohydrates and Amiles in Non-Aqueous Solvents”. Asian Journal of Chemistry, vol. 6, no. 4, July 2012, pp. 801-6, https://asianpubs.org/index.php/ajchem/article/view/24678.