refdb uses XML files to encode the information about the required references for a bibliography. The resulting bibliographic output can be used as an external entity in both XML and SGML DocBook files (the bibliography can be transformed to any other SGML or XML type with suitable stylesheets). The structures of these files will be briefly explained in this chapter.
refdb uses (Open)Jade (for SGML documents) or an XSLT processor (for XML documents) to extract a list of required references and their logical relationships (position in the document, single or multiple citations and such). This list is encoded in an XML document conforming to the CitationList XML DTD.