BibTeX is a freely available citation management tool for LaTeX documents. It is a program and a file format used to describe and process lists of references, mostly for LaTeX documents. BibTeX comes bundled as standard with LaTeX. A formatted BibTeX file can be converted to a bibliography of any format, using a third-party converter of some kind. BibTeX allows you to store references in an external, flat-file database which can be linked to any LaTeX document. References in the database can then be cited in the document.