Viswanathan, M., and G. Krishnan. 2010. “Synthesis and Characterization of Mixed Ligand Complexes of Praseodymium(III), Neodymium(III), Samarium(III), Gadolinium(III) and Dysprosium(III) With Piperidinobenzylurea”. Asian Journal of Chemistry 16 (1):156-62. https://asianpubs.org/index.php/ajchem/article/view/19556.