“…Yang et al developed invariant energy quadratization (IEQ) approach [56,59,60,[63][64][65], which leads to linear, unconditionally energy stable numerical schemes [58]. The scalar auxiliary variable (SAV) approach [44][45][46] was proposed by Shen and his collaborators, and has been applied to construct linearly energy stable numerical schemes [32,33,40]. In References [7,8,21,22,26,[36][37][38][39], the authors extended the IEQ or SAV approach to design linear, energy stable numerical schemes.…”