S Chandra,
LK Gupta - Spectrochimica Acta Part A: Molecular and …, 2004 - Elsevier
Cobalt (II), nickel (II) and copper (II) complexes having the general composition M (L) X2
(where M= Co (II), Ni (II) and Cu (II), L= ligand, ie 3, 4, 12, 13-tetraketo-2, 5, 11, 14, 19, 20 …