L. Singh, U. Singh, and D. K. Sharma, “Synthesis and Magneto-spectral Studies of Cobalt(II) and Nickel(II) Complexes of 4[N-(p-Dimethylaminobenzalidene) Amino] Antipyrine Semicarbazone ”, ajc, vol. 14, no. 1, pp. 484–488, Mar. 2010.