# How can I reference a page in another pdf, which I have no control over?

I want to reference a specific page in another pdf document. There is also a bookmark on that page, which I could use.

However, I have no control over the other document, and maybe it wasn't even created with Tex.

Is there a way to extract labels from the file that I could use with \hyperref or xr, or which other packages or commands could I use?

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Usually you refer to other (external) sources by citing them, e.g. \cite. As far as i understood, \ref is really made only for inernal referencing. –  Ruben Aug 12 '13 at 9:26
This would be nice for referencing in large document packs. –  Forkrul Assail Aug 12 '13 at 18:22
The beginning of your question seems to imply you know the page you want to open to; Adobe's documentation at adobe.com/content/dam/Adobe/en/devnet/acrobat/pdfs/… has examples of opening pdf documents via URL (I would guess a "file://" would work too). So now the issue is to create a clickable URL in your document. I am puzzled by the second part of your question: Even if you extracted all the labels in the file, how would you know which specific label to target? –  user1823664 Aug 13 '13 at 13:50
Well, I could try them all or at least hope that they are named somewhat reasonable so that I can identify the one I need. That link you provided mentions "named destinations", that looks promising. I'll see if I can extract those from the document. –  Arian Aug 13 '13 at 14:15

If the external PDF is generated with pdflatex without labels or with another program as LibreOffice, you can use \href of package hyperref with the option [page=x]. Example:

\documentclass{article}
\usepackage{hyperref}
\begin{document}
Some text.
\href[page=4]{external.pdf}{See page 4 of the external PDF}
\end{document}


Unfortunately, this work with Acrobat Reader but not with others as Evince, for example. This is a problem of the viewer, not the LaTeX code.

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user1823664's documentation link gave me another lead.

In Acrobat, under View > Show/Hide > Navigation Pane > Destinations one can find a list of destinations in the document. They can be referenced via

\href{external.pdf#thedestination}{See other stuff of the external PDF}

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