If you have appropriate privileges, you can add pages from one image document to another by dragging a thumbnail from one viewer window onto the Pages toolbar of a document in another viewer window.
You cannot add pages to read-only documents, to non-image documents, or to non-revisable documents that have a different file type than the added pages. If you attempt to do so, the system displays a warning indicating why the pages could not be added.
To add pages to an image document: