...
If you are contributing 3D material because you want it to be discoverable via the Europeana website then you need to provide, as a minimum, either a link to the 3D content (via a viewer or a link to a direct object) or a link to a website in which the file can be viewed online (both in the edm:isShownBy property). Note that embedding 3D content into PDF documents is not a recommended format for new content.
...