[ Note: the last three are not unique; there are other pairs with
        frequency 29. ]

1. CD: WxWF0KgyrE4OTvbBmESu   BOOK: wCqTcUftM9ImxM0b5W8h   ( 31 )
2. CD: FPEqwaLCsUrPH002YDMx   BOOK: WzkNZgIkMt7XGWQCxyqC   ( 31 )
3. CD: wuOvpaxTpWmglvnHF94u   BOOK: l4W9zVGmwZILF4aihT8C   ( 31 )
4. CD: hO9bovjyNeY8L7nwLQ08   BOOK: ok6i0BZYOVFrxIIb03bg   ( 30 )
5. CD: dqa8P2brDvhcCNk2o7mw   BOOK: 3GrP3pimBlMCgpuPHqIc   ( 30 )
6. CD: wdx2Sq95sMDnNZazrLLp   BOOK: RYaXW8fQpYl3nX3XwD42   ( 30 )
7. CD: iasCrwfefJxvGkMaD54H   BOOK: 74dokbpkSUHNLIk04Ufz   ( 30 )
8. CD: 3Milx13FQdVKCzVcmeyF   BOOK: Ihf50zmQWHbH84uM6W1x   ( 29 )
9. CD: L2URVSJ9xcwfsjLbV0hQ   BOOK: ET4UCh9Qgjrj8jYFJFUj   ( 29 )
10. CD: cH4Fb2bN2m4IFwmfNT2z   BOOK: 6mJyDlZUFON8uTNny3xb   ( 29 )