Validator fails on this ISBN10 number
tmaier opened this issue · 0 comments
tmaier commented
1.9.3-p286 :001 > require "isbn"
=> true
1.9.3-p286 :002 > ISBN.valid? "3-540-49698-x"
=> false
But this book exists
https://portal.dnb.de/opac.htm?method=simpleSearch&query=3-540-49698-x