Collaborating or sharing manuscripts across different computers

Citations is one of Papers' most loved features. Combine the possibility of sharing your library across different computers (whether Mac or PC), and the possibility of collaborating with others in your field, and it is not out of the question that you may add citations to your manuscript on different computers.

There are a few things to keep in mind, or be aware of, if you are using Papers on different computers or collaborating on manuscripts with other Papers users.

Writing a manuscript using different computers

If you are syncing your Papers library across different computers, you are unlikely to run into any issues with Citations. As long as you are accessing the same library when you work on your manuscript, you should not see any discrepancies in your citekeys.

If you are not syncing your library across computers, you may need to have at least one library where you have collected all articles you are citing in your manuscript. For example, your work library might have citations 1-10, and your home library may have citations 20-30. However, before formatting your manuscript you need to make sure citations 1-10 are also on your home computer if that is where you will be formatting the manuscript. If you are adding these citations independently (through drag and drop, downloading directly inside Papers, or any other way that is not syncing your library or exporting your library from one Papers copy and importing it to the other), you may experience a situation where some citekeys look different across your libraries.

For example, on one library the citekey may look like {Authorname:2010jb}, and in your other library the citekey may look like {Authorname:8RPYbjS+}. Each of these can correspond to the same article in your library, but you may imagine that if you entered the second citekey on your work computer and format on your home computer containing the first citekey format, Papers will not recognize the citekey.

Having said this, the only situations where this is really problematic is if you are entering the citekeys by copying and pasting them into your document, or if you are entering them into a document not created in MS Word. When using Word and entering citekeys with Citations, the field codes in Word will be populated with the information from your library. So, the citekey themselves really do not matter and you can still format your manuscript on either computer. In this case, there is no need to worry about the discrepancy in citekeys.

How Papers assigns citekeys to your articles

This discrepancy can happen in the scenario described above because of the way Papers assigns citekeys to articles. When an article is imported, Papers assesses whether the meta data associated with the article looks complete or feasibly reliable. If this is the case (we won't bore you with the technical details), Papers assigns a citekey with the format {Authorname:2010av}, the date is the publication date of the article and letters are added at the end to ensure each citekey is unique.
In particular, this citekey format is assigned when the doi is included in the meta data of your article.

When the doi is not included and if the meta data is deemed incomplete or potentially unreliable Papers assigns a citekey in the format {Authorname:lettersandnumbers}. This citekey would not be a universal citekey for that article, but is unique to your library.

A citekey like this is still recognized on the computer on which it was created even if you type out the citekey or copy and paste it into a document. Again, when using MS Word and Citations to enter the citekeys, you will not have anything to worry about.

Working on a manuscript with a collaborator

When you are working on the same manuscript with a collaborator who is also using Papers, the same concepts described above apply.

Resolving citekey inconsistencies across libraries

The best way to address this situation if it occurs to you across your libraries, is to ensure each article has complete meta data prior to inserting the citekey in your manuscript.

You can do so by matching your articles to a repository, or entering the information manually, including the doi. If you are collaborating and sharing a manuscript back and forth, the best strategy is to enter all citekeys using Citations in Word. If you are not using Word, or if at least some of the citekeys are typed our or pasted into the document, one strategy could be to share the articles you are citing using a shared collection using Papers Online, or exporting one of the libraries as an XML file and importing it to the library that will be used to format the final manuscript.