The authors author would like to thank Fundação para a Ciência e Tecnologia (FCT) - Portugal the financial support for the PhD grants with references SFRH/BD/74263/2010 and SFRH/BD/87392/2012; Biometrics represents a return to a natural way of identification: testing someone by what (s)he is, instead of relying on something (s)he owns or knows seems likely to be the way forward. Biometric systems that include m...