| well-formed | ||
| no hyphens provided | ||
| ISBN-10 | 1-78110-987-7 | 1781109877 |
| ISBN-13 | 978-1-78110-987-8 | 9781781109878 |
| Agency | English language | |
| Publisher | Pottermore Publishing | |
| well-formed | ||
| valid hyphenation | ||
| ISBN-10 | 977-14-3300-8 | 9771433008 |
| ISBN-13 | 978-977-14-3300-2 | 9789771433002 |
| Agency | Egypt | |
| Publisher | Nahdet Misr | |
| not well-formed | |||||||||
| valid hyphenation | |||||||||
| The check-digit is not correct. If the rest of the ISBN is correct (and it may not be), the check digit should be: 8. | |||||||||
| Correcting check-digit gives: 977-14-3300-8 which appears to be valid. The governing agency is: Egypt. | |||||||||
| not well-formed | |||||||||
| no hyphens provided | |||||||||
| The UCC prefix is malformed (should be 978 or 979). | |||||||||
| The check-digit is correct. | |||||||||
| well-formed | ||
| no hyphens provided | ||
| ISBN-10 | 1-78110-762-9 | 1781107629 |
| ISBN-13 | 978-1-78110-762-1 | 9781781107621 |
| Agency | English language | |
| Publisher | Pottermore Publishing | |
