[AccessD] ISBN, ISBN-13, calculation of check digits

Hi all

If you deal with books and ISBN numbers and the upcoming ISBN-13 (from
year 2007), this page may be of interest:

  http://www.bisg.org/isbn-13/publishers.faq.html 

and the link to Conversions and Calculations:

  http://www.bisg.org/isbn-13/conversions.html 

Note the move from Modulus 11 to Modulus 10 check digit calculation as
in EAN-13.
Also note the use of X in the old ISBN numbers to represent check digit
10.

/gustav