Kumar Kathal, Mahesh, and R.K. Gautam. “Synthesis and Characterisation of Mixed Copper(II) Complexes With 2,2´ -Bipyridine &Amp; 1, 10-Phenanthroline ”. Asian Journal of Chemistry, vol. 4, no. 2, Mar. 2010, pp. 357-60, https://asianpubs.org/index.php/ajchem/article/view/25050.