Previous: Reference Styles, Up: Labels and References

3.7 xr: Cross-Document References

The LaTeX package xr makes it possible to create references to labels defined in external documents. The preamble of a document using xr will contain something like this:

     \usepackage{xr}
     \externaldocument[V1-]{volume1}
     \externaldocument[V3-]{volume3}

and we can make references to any labels defined in these external documents by using the prefixes ‘V1-’ and ‘V3-’, respectively.

RefTeX can be used to create such references as well. Start the referencing process normally, by pressing C-c ). Select a label type if necessary. When you see the label selection buffer, pressing x will switch to the label selection buffer of one of the external documents. You may then select a label as before and RefTeX will insert it along with the required prefix.

For this kind of inter-document cross-references, saving of parsing information and the use of multiple selection buffers can mean a large speed-up (see Optimizations).