Structural and magnetocaloric properties of nano Zn ferrite doped with Ni under hydrothermal conditionsA. Tawfik, O. M. Hemeda, D. M. Hemeda and M. MostafaEur. Phys. J. Plus, 129 12 (2014) 278DOI: https://doi.org/10.1140/epjp/i2014-14278-8