A method for authenticating a document including: radio frequency scanning
at least a portion of the document; optically scanning the document;
generating a document data dependently upon the radio frequency scanning
and optical scanning; comparing the generated data to stored data, the
stored data being previously generated dependently upon a prior radio
frequency scanning of the portion of the document and prior optical
scanning of the document; and providing an output indicative of the
document being authentic if the generated data is sufficiently identical
to the stored data as determined by the comparing.