Entity reference value from url in node add form block I have a content type book and another content type pages.
A page has a entity reference field to book.
Now, I want to allow users to create pages on the same page as book. So, I created a page add form using formblock module.

I would like to have the entity reference field auto generated and pointing to the book. 

Is it possible? 
Thanks. :)
Node Reference URL Widget can help you :)