“Synthesis, Characterization and Spectral Studies of Y(III), La(II) and Rh(III) Complexes With 2,4-Dimethyl-6-(4-Nitro-phenylazo)Phenol ”. Ibn AL-Haitham Journal For Pure and Applied Sciences, vol. 29, no. 1, Mar. 2017, https://jih.uobaghdad.edu.iq/index.php/j/article/view/50.