Mendeley and Elsevier continue to support the CSL project

For the second consecutive year, Mendeley supports the open source Citation Style Language (CSL) project with a US$ 5,000 donation. With CSL, Mendeley users can format their citations and bibliographies in over 1,200 different citation formats, covering more than 7,500 scientific journals.

Mendeley recently (1) made it much easier to use CSL styles into your preferred language. In this guest post, CSL developers Rintze Zelle and Sebastian Karcher describe how this works.

Say, for example, that you wish to publish an article about Barcelona’s recent Champions League victory—in your native Catalan—and therefore need a Catalan citation style. At first glance, things might look bleak. If we go to the “View” menu, select “Citation Style” and then “More Styles…”, switch to the “Get More Styles” tab, and search for “Catalan”, we don’t see a lot of results:


Fortunately, you can actually use any style you want in Catalan. If we select the “Chicago Manual of Style 16th edition (author-date)” style, a reference to a book chapter will be in US English by default and look something like:

Mares, Isabela. 2001. “Firms and the Welfare State: When, Why, and How Does Social Policy Matter to Employers?” In Varieties of Capitalism. The Institutional Foundations of Comparative Advantage, edited by Peter A Hall and David Soskice, 184–213. New York: Oxford University Press.

To use the style in Catalan, you can open the Citation Style window again (“View” → “Citation Style” → “More Styles”). In the “Installed” tab, look for the “Citation and Bibliography Language” drop-down menu. When set to “default”, styles localize to their own language (and US English if no language is set as default). The menu further includes with the 50 languages CSL styles can automatically localize to, from Afrikaans to Welsh. Let’s pick “Catalan”.


If we now create the same Chicago Manual of Style reference again, it will be in Catalan:

Mares, Isabela. 2001. «Firms and the welfare state: When, why, and how does social policy matter to employers?» En Varieties of capitalism. The institutional foundations of comparative advantage, editat per Peter A Hall i David Soskice, 184-213. New York: Oxford University Press.

Notice how this didn’t just change the vocabulary (“In” turned into “En”, “edited by” into “editat per”, and “and” into “i”) but also the quotation marks. Localization of CSL styles further extends to date formats, ordinal numbers, and other punctuation.

How Does It Work?
For those interested in a bit of technical background, here goes: To allow for automatic localization, the Citation Style Language defines a fixed set of terms that are translated to the various locales in separate “locale files”. When a CSL style uses one of these terms, the proper translation is automatically selected. For example, the CSL code that resulted in “edited by Peter A Hall and David Soskice” and “editat per Peter A Hall i David Soskice” in the examples above is:

<names variable=”editor translator” delimiter=”. “>
<label form=”verb” text-case=”capitalize-first” suffix=” “/>
<name and=”text” delimiter=”, “/>

This prints the translation of “editor” term (of form “verb”) from the US English or Catalan locale files in front of the names of the editors.

What If My Language Is Missing or Incorrect?
At CSL headquarters, we are fluent in only a handful of languages. So, if your favorite language is absent from the drop-down menu, you might be the best person to help us add it! Just follow our translation instructions, and feel free to ask for help at the CSL locale file issue tracker. You can also use the issue tracker to suggest better translations for existing CSL locale files.

Some CSL styles will localize better than others. E.g. if a style doesn’t use the “editor” term but directly uses “edited by”, this string cannot be automatically translated. The same holds for punctuation and dates: only styles that fully rely on the CSL locale files can properly localize. If you come across styles that don’t fully localize, you can either contact Mendeley support (who often pass your comments on to us), or create an issue at the CSL style issue tracker.

Finally, there are some limits in CSL when it comes to localization, and CSL might not support all the idiosyncrasies of your preferred language. While we hope to keep improving localization support in future versions of CSL, for now you can either correct such issues by hand after generating your bibliographies, or create a CSL style dedicated to your language.

We hope you enjoy the improvements, but let us know what you think in the comments or via the feedback channels above!

1. The features described in this post were introduced in Mendeley Desktop v1.13.4.
2. All non-English locale-specific CSL styles include their locale in the style name (in English). E.g. “Archéologie médiévale (French)”.