M. M. Alam, R. Begum, S. M. M. Rahman, and S. M. S. Islam, “Synthesis, Spectroscopic and Electrochemical Studies of Mononuclear Fe(II) and Ni(II) Complexes Containing a Macrocyclic Ligand Derived from Pyridine-2,6-dicarboxaldehyde and 1,2-Bis(2-aminoethoxy) Ethane”, J. Sci. Res., vol. 3, no. 3, pp. 599–607, Aug. 2011.