As a self-publishing service, Blurb does not review, edit or monitor the content of books published using our services. This means we cannot tell you if a specific image, poem, etc is licensed or "safe" for you to use.
If you're looking for content for your book, creative commons includes resources for some licensed material. You can also search for "public domain" material.
You should carefully check the license for any content you wish to use. Using content that you don't have permission (a "license") to use will violate our terms and conditions.