ARTICLE Hadid_SIGPRO_2015/IDIAP Biometrics systems under spoofing attack: an evaluation methodology and lessons learned Hadid, Abdenour Evans, Nicholas Marcel, Sébastien Fierrez, Julian Anti-spoofing Biometrics Spoofing EXTERNAL http://publications.idiap.ch/attachments/papers/2015/Hadid_SIGPRO_2015.pdf PUBLIC IEEE Signal Processing Magazine 2015