Short-range and long-range magnetic interactions. (a) M–T and (b) d M / d T –T curves for SMP and MMP magnets upon heating at 2 °C/min under 200 Oe. Initial magnetization curves and recoil loops on the demagnetization curve for 9 wt.% La–Ce containing (c1) SMP and (c2) MMP magnets. The corresponding dependences of μ M irr and μ M rev for the SMP and MMP magnets on the applied reversal field are shown in (c3) and (c4), respectively. Calculated μ χ irr as a function of reversal field for the SMP and MMP magnets are given in (c5) and (c6), respectively.^[22]