@ARTICLE{6196158, author={Jiang, Tingting and Zeng, Huacheng and Yan, Qiben and Lou, Wenjing and Hou, Y. Thomas}, journal={IEEE Wireless Communications Letters}, title={On the Limitation of Embedding Cryptographic Signature for Primary Transmitter Authentication}, year={2012}, volume={1}, number={4}, pages={324-327}, doi={10.1109/WCL.2012.050112.120059}}