V. N. Nikolić, M. D. Gilić, and V. V. Spasojević, “Characterization of NiO nanoparticles prepared using gelatin and a low-cost synthesis”, Vojnoteh. glas., vol. 67, no. 1, pp. 36–52, Sep. 2018, doi: 10.5937/vojtehg67-18535.