ISBN
Internation Standard Book Number: A 9 digit number, divided with hyphen with a control digit, which can be 0...9 or X.
Value type of the APE Key ISBN.
 
Check of correctness:
N1 N2 N3 N4 N5 N6 N7 N8 N9 - Nchk
The following equation must be fullfilled:
(2 N1 + 3 N2 + 4 N3 + 5 N4 + 6 N5 + 7 N6 + 8 N7 + 9 N8 + 10 N9) MOD 11 = Nchk
A value of 10 for Nchk is encoded as a X.
Examples:
-  3-89319-434-7
-  3-05-500074-9
-  0-201-54199-8
-  3-341-00480-7
-  3-341-00488-X
 
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