The EAN frontend is similar to UPC; it accepts strings of
digits, 12 or 7 characters long. Strings of 13 or 8 characters are accepted if
the provided checksum digit is correct. I expect most users to feed input without
a checksum, though. The add-2 and add-5 extension are accepted for both the EAN-13
and the EAN-8 encodings. Note: You can get an EAN code for your product by visit the European EAN
Code Council's web page at http://www.ean.be
