refentry.source.fallback.profile string refentry.source.fallback.profile Specifies profile of "fallback" for refentry "source" data refmeta/refmiscinfo[not(@class = 'date')][1]/node() The value of refentry.source.fallback.profile is a string representing an XPath expression. It is evaluated at run-time and used only if no "source" data can be found by other means (that is, either using the refentry metadata-gathering logic "hard coded" in the stylesheets, or the value of the refentry.source.name.profile and refentry.version.profile parameters, if those are enabled). Depending on which XSLT engine you run, either the EXSLT dyn:evaluate extension function (for xsltproc or Xalan) or saxon:evaluate extension function (for Saxon) are used to dynamically evaluate the value of refentry.source.fallback.profile at run-time. If you don't use xsltproc, Saxon, Xalan -- or some other XSLT engine that supports dyn:evaluate -- you must manually disable fallback processing by setting an empty value for the refentry.source.fallback.profile parameter.