“…More recently, this model has attracted a fresh surge of theoretical attention [20,32,33,34,35,36,37,38,39], partly due to the appearance of materials whose spin physics is described by this model (see references in [20,32]). Most studies concentrate on finite magnetic fields or finite temperatures and on properties in the thermodynamic limit [20,28,29,30,31,32,33,34,35,36,37,38], or very near the transition point atβ = 4 [27,34,39,40].…”