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ISBN - Wikipedia
What Is an ISBN and How to Get It? Your Definitive Guide to ISBN
International Standard Book Number | ISBN, Identification, …
What is an ISBN? | International ISBN Agency
About the ISBN standard | ISBN.org
FAQs: General Questions | ISBN.org
ISBN and ISSN Systems: General Information and Resources
ISBN Definition & Meaning - Merriam-Webster
ISBN Definition & Meaning | Dictionary.com
ISBN | English meaning - Cambridge Dictionary