Hi Mary,
Since the OCLC service seems to be widget that can be launched/viewed/used in an iframe, have go at using it with the HTML block, a label or basically any place where you'd have access to the (ATTO or TinyMCE) text editor. Open the HTML editing interface by using the </> button and paste your code to see if it works.
I've successfully added Twitter widgets that way, and it'll probably work with this one as well.