Comments on “State space modeling and stability theory of variable fractional order systems”

With several counterexamples, it is pointed that the commutative law and the principle of superposition of fractional calculus are invalid. The so-called variable order state space modeling method proposed in the above research paper mentioned in the title does not hold. The proof of judgement theorem for stability addressed in the above paper is lack of theory evidence. A counterexample is provided to show the contradiction between the condition and the conclusion of stability theorem.