Magneto Caloric Properties of Polycrystalline Gd2O2S for an Adiabatic Demagnetization RefrigeratorH. Fukuda, Y. Kobayashi, R. Arai, K. Baba, H. Nakagome and T. NumazawaMATEC Web Conf., 109 (2017) 04004DOI: https://doi.org/10.1051/matecconf/201710904004