Integrate Google Book Search into a PHP application

Integrate Google Book Search into a PHP application: "Google Books allows Web application developers to access book lists and metadata through its REST-based developer API. The Zend Framework's Gdata module is able to process the XML feeds generated by this API and use it in the context of customized Web applications. This article introduces the Google Book Search Data API, demonstrating how you can use it to search for books by keyword, author, and title; retrieve book thumbnails and previews; and add reviews and labels to user libraries."