“…The suggested criteria apply to various FCO-LTI systems, both single and multiple in fractional-order calculus, scalar and multivariable in input-output dimension, including the regularorder systems as the special cases. To extend the idea to other complicated fractional-order systems, say time-delayed [18], stochastic [19,20] and hybrid ones [21] are among our subsequent topics. Also interestingly, the factors β( ⋅ , ⋅ ) and α( ⋅ , ⋅ ) may be utilised for stabilisation [4,[22][23][24] or disturbance rejection [2] as design freedoms.…”