How to get DOI links in bibliography

Include your DOIs in the BibTeX database under the doi field and include the URLs under the url field; for example:

\begin{filecontents*}{test.bib}
@article{foo2010,
  author = "Foo Bar",
  journal = "J.P.B.",
  year = 2010,
  title = "Where the wild things are.",
  doi = {10.1.1/jpb001},
  url = {http://dx.doi.org/10.1.1/jpb001}
}
\end{filecontents*}

\documentclass{article}
\usepackage{natbib,hyperref}
\begin{document}
test \citet{foo2010}
\bibliographystyle{plainnat}
\bibliography{test}
\end{document}

If you wish to hyperlink the DOI, I believe that loading the doi package will perform this automatically.

A minimal change would be to use the plainurl style instead of plainnat.

You could also continue to use plainnat and give a suitable definition of \doi (to override the non-hyperlinked version \provided by plainnat), eg:

\newcommand*{\doi}[1]{\href{http://dx.doi.org/#1}{doi: #1}}

In both cases, just use a doi field in your .bib file.

I came across this thread recently while solving a variant of Peter's question.

Instead of adding a hyperlink DOI to each of the bibliography items, you may want not to write the DOI explicitly but to make another field of the bibliographic item clickable with an hyperlink to the download location. In some journals, the hyperlink is associated to the group "Journal Name, volume, page number" for instance. You may find some existing bibliography style files doing that, but sometimes you need to add this feature to a personal bibliography style. In this case, none of the above solutions work. The hack I came up with is to define the following function in the .bst file:

FUNCTION {doilink}
{ duplicate$ empty$
{ pop$ "" }
{ doi empty$
    { skip$ }
    { "\href{http://dx.doi.org/" doi * "}{" * swap$ * "}" * }
  if$
}
if$
}

Here is an example of how to call the function:

FUNCTION {format.vol.num.pages}
{ volume field.or.null
  boldface
  pages empty$
    'skip$
    { duplicate$ empty$
    { pop$ format.pages }
    {  ", " * pages first.page.number * }
      if$
    }
  if$
  doilink
}

In this case the volume and pages will be hyperlinks. In general the hyperlink will be associated to the item on the top of the stack when the function doilink is called. You also need to make sure that the doi is declared as a possible field for bibliographic entries. As a minimal example:

ENTRY
{ author
  doi
  journal
  key
  pages
  title
  volume
  year
} 

This may not be the most robust solution but it solved my problem. I thought it might be useful to some people here.

EDIT

Following @laclaro 's follow-up question, I add an example of a .tex file calling the modified .bst file:

\documentclass{article}

\usepackage{natbib}

\usepackage{color}
\definecolor{darkblue}{rgb}{0.,0.,0.4}
\definecolor{darkred}{rgb}{0.5,0.,0.}

\usepackage[pdftex,colorlinks=true,linkcolor=darkblue,citecolor=darkred,urlcolor=blue]{hyperref}

\usepackage{filecontents}

\begin{filecontents}{\jobname.bib}
@article{Brune1996,
    Author = {Brune, M  and Hagley, E and Dreyer, J and Maître, X and  Maali, A and Wunderlich, C and Raimond,J.M. and Haroche,S },
    Title = {Observing the Progressive Decoherence of the “Meter” in a Quantum Measurement},
    Year = {1996},
    Journal = {Phys. Rev. Lett.},
    volume = {77},
    pages = {4887},
    doi = {10.1103/PhysRevLett.77.4887}}
\end{filecontents}


\begin{document}

\cite{Brune1996}

\bibliographystyle{mystyle}
\bibliography{\jobname}

\end{document}

and a screenshot of what it looks like:

Here, clicking on the volume or page number opens the doi link. To adapt this so that the hyperlink is on the journal, you would need to modify the function FUNCTION {format.journal} in the .bst style file rather than the FUNCTION {format.vol.num.pages} as was done here.