WakgariBungulaNegessa, WondimuTesfa Tefera, Tegene Desalegn Zeleke, and HadguHaliekiros Belay, “Chemical Speciation of Complexes of L-phenylalanine and maleic acid with toxic metal ions in Dimethylformamide -Water Mixtures”, IJPDA, vol. 6, no. 9, pp. 578-591, Sep. 2018.