# referencing labels from other files [duplicate]

Sometimes I want to refer (using \ref) a \label from some other tex file. What is the right way to do it?

(It's, of course, possible to \include all files in one and then use \includeonly — but it breaks e.g. page and section numbering.)

http://www.tex.ac.uk/cgi-bin/texfaq2html?label=extref

## Referring to labels in other documents

When producing a set of inter-related documents, you’ll often want to refer to labels in another document of the set; but LaTeX, of its own accord, doesn’t permit this.

So the package xr was written: if you say

\usepackage{xr}
\externaldocument{volume1}


(...)

• The package looks for the aux file, so it does not work in all settings and, more importantly, without a full document. (Which is fair, but noteworthy for unwary readers.) Nov 7, 2013 at 16:38
• @Ulrike Fischer: Could you please explain how I an do the reverse at the same time? For instance, if I want to call a reference from the the 'present document' into the the 'volume1'? Jan 16 at 4:16