To create a direct link to your book on Apple Books, use the Apple Books Marketing Tools.
You can also create your own link based on the book's ISBN. There are two ways to construct a URL for your book using its ISBN number.
Apple Books-specific link example:
<a href="http://itunes.apple.com/us/book/isbn9781451648553">Steve Jobs, by Walter Isaacson</a>
Generic ISBN link:
<a href="urn:isbn:9781451648553">Steve Jobs, by Walter Isaacson</a>
See Using International Standard Book Numbers as Uniform Resource Names for information on how International Standard Book Numbers (ISBN) can be supported within the Uniform Resource Names (URN) framework.
At the end of flowing books, Apple Books automatically includes links to other books by the same author, prioritized by popularity.