On the unlinkability of randomization-enhanced Chaum's blind signature scheme

Fan, Chen and Yeh proposed a randomization-enhanced Chaum's blind signature scheme in 2000. Recently, Li, Zhang and Kou claimed that Fan et al.'s blind signature scheme cannot satisfy the unlinkabilty property of the blind signature. However, this letter demonstrates that Li et al.'s claim was wrong, i.e., Fan et al.'s blind signature scheme still holds the unlinkability property.