Susceptibility and saturation magnetization versus temperature for three selected samples. The solid and dashed curves indicate heating and cooling, respectively. In the plots of saturation moment, the open symbols refer to cooling curves: the open circles indicate cooling from 175°C to room temperature, the open diamonds indicate cooling from 275 to 175°C, the open triangles indicate cooling from 475°C to room temperature, and the open squares indicate cooling from 580°C (595°C in some cases) to room temperature. The solid squares indicate the values measured during heating.