Citation Style Language 1.0

Posted by Rintze M. Zelle

The Citation Style Language (CSL) team is proud to announce CSL 1.0, a free and open XML language for the formatting of citations and bibliographies.

A New Home is the new home of the CSL project, hosting the schema, documentation, project news, and more. In the near future will also host the style repository currently found at

By Academics, for Academics

CSL 1.0 has been developed by academics, for academics. The members of the development team hail from diverse fields, covering social science, law, and natural science. We are keenly aware of the diverse and demanding requirements of scholars working in different languages and different fields of research. At the end of an intensive year of development work, we feel confident that CSL 1.0 marks an important step forward in academic productivity.

New features

The top 5 new features that we would like to highlight:

  • In-field markup: CSL 1.0 compatible programs now support markup within titles, with support for superscript, subscript, small capitals, italics and boldface.
  • Full localization: whereas CSL 0.8 only offered localization of terms, CSL 1.0 offers full style localization, adding support for localized dates and punctuation.
  • Names: many new features are related to names. Name disambiguation has been refined, and name particles (“van” in “Ludwig van Beethoven”) can now be sorted and rendered according to conventions that reflect the culture and personal preferences of each author.
  • Documentation: the schema for the 1.0 release is accompanied by a full set of documentation. A specification gives all the details on CSL 1.0, and upgrade notes discuss the changes made between CSL 0.8 and 1.0. A primer offers a concise tutorial on editing CSL 1.0 styles.
  • CSL processors: CSL 1.0 is released alongside citeproc-js, the first CSL 1.0 compatible CSL processor, as well as a CSL 1.0 test suite. Various features of CSL 1.0 and citeproc-js can be seen in action in the online demo. Adding support for CSL was never easier.

CSL 1.0 includes many more improvements. For a full overview, see the upgrade-notes.

Using Existing Styles

Zotero support for CSL 1.0 is scheduled for Zotero 2.1. When released, the Zotero team will upgrade the more than thousand CSL 0.8 styles hosted in the Zotero Style Repository. To upgrade a CSL 0.8 style yourself, follow the upgrade procedure.