Scott Bolinger

GTINs (Global Trade Item Numbers) including UPC, EAN, and ISBN are globally recognized unique identifiers for products.
They are required to list your product on Google and Amazon, this plugin allows you to add your GTIN and display it on your product page.
Supports:
<ul>
<li>Simple products</li>
<li>Variable products</li>
<li>Composite products</li>
<li>Product bundles</li>
</ul>
Features:
<ul>
<li>Add GTIN for main product</li>
<li>Add unique GTINs for product variations</li>
<li>Option to display GTIN on the single product page</li>
<li>Change GTIN to any other text</li>
<li>Add GTIN to structured product data</li>
<li>Works with product feeds like Google Shopping and more (requires a feed plugin)</li>
</ul>

WooCommerce UPC, EAN, and ISBN

Awesome plugin with great code

Add GTIN codes like UPC, EAN, and ISBN to your WooCommerce products.

Stephan Elst

This plugin allows you to share your the books you are currently reading as a widget on your WordPress page, without the use of an API.
The plugin will display the following data, title, author, cover image and progress. The widget can link to the books and authors page on goodreads. It can display the content in two layouts, compact and long.
Please note that your profile has to be set to public.

Share Goodreads Update

Widget to give an overview of your currently reading books on goodreads, whitout the use of API.

WooCommerce UPC, EAN, and ISBN vs Share Goodreads Update