S. Thakur, S. Brat Singh, and S. Kumar, “Synthesis and Characterization of Co(II), Ni(II) and Cu(II) Complexes with a Macrocyclic Ligand 5,7,12,14-Tetramethyldibenzo (b, i)-1,4,8,11-Tetraaza Cyclotetra Dec-2,4,6,9,11,13-Hexaene”, ajc, vol. 13, no. 3, pp. 1001–1005, Mar. 2010.