You can use the website or software to use the book number and the CIP-verified number to conduct online inquiries. Usually, there is a nuclear number after the book's ismn or CIP number. It is the book's serial number. The following steps can be used to check the VIP number on the Internet: 1. Open the National Library or various e-book websites. 2 Enter the book number or the IDN in the search box and click the search button. 3. You can see all the information about the book in the search results page, including the CIP-approved number. 4. You can use this CIP-verified number to search the database of the National Library or other digital libraries to obtain more information about this book. By checking the number of a book, one could easily and quickly find out the information of a book, its publication status, edition, reader reviews, and so on.