  In this comment, we want to emphasize that when the state of the two qubit is
$|0>_{B}|1>_{A}$ or $|1>_{A}|0>_{B}$, Bob's Bell basis measurement outcome can
not be $|\phi ^{\pm}>$. Also, when the product state is $|0> |0>$ or $|1> |1>$,
Bob's measurement outcome can not be $|\psi ^{\pm}>$.
