“…The second assertion of Theorem 1.1 is presented in [13,Theorem 25,Theorem 26] and [20,Theorem 1.1]. By exploring ord p (h n (G)), we confirm [13,Theorem 25] and [20,Corollary 8.2] (cf. [18,Theorem 1.4]) with relation to the case where equality holds, namely, Theorem 1.…”