A Banach space X is called
quasi-reflexive (of order n) if codimX∗∗π(X) < +∞(codimX∗∗π(X) = n), where π
denotes the canonical embedding of X into its second conjugate x∗∗. R. Herman and
R. Whitley have shown that every quasireflexive space contains an infinite
dimensional reflexive subspace. In this paper this result is extended by showing that
if X is quasi-reflexive of order n and 0 ≦ k ≦ n then X contains a subspace which is
quasi-reflexive of order k.