If you have a document (or more than one document) to upload you are in the right place.
If your document is online and you don’t have the file to upload, use the Web Content option instead of this one. If your document is a jpeg then upload it as an Image.
What to do? First, add all references (author, title, etc.) for your document in the Document info section–click on the “Add Reference for another Document” button for more than one reference. Then using the Document Upload interface, upload the files–most documents should be in PDF format.