“…A number of modeling strategies for these compounds have been proposed but three stand out in the sense that they provide unified frameworks for characterizing hysteresis in ferroelectric, ferromagnetic and ferroelastic materials, which are collectively referred to as ferroic compounds. These three approaches are the following: (i) homogenized free energy models [9,13,18], (ii) Preisach formulations [1,2,12,19], and (iii) domain wall models [6,8,11,14,15]. The first two are formulated as integral equations whereas the domain wall models are typically posed as differential equations.…”