The most common way to use a DOI is to append it to the
http://dx.doi.org/ URL. The web server at that URL redirects you to the URL where the actual content of that DOI is hosted. These destination URLs are typically on the web server of some journal, publisher or conference website.
However, the DOI server also provides other services besides redirection. You can get the BibTeX entry for a DOI if you query with a HTTP header where the Content type is
Here is a tiny Bash script that takes a DOI as input and returns the BibTeX from the DOI server using Curl:
#!/bin/bash url="http://dx.doi.org/"$1 curl -LH 'Accept: application/x-bibtex' $url
Tried with: Curl 7.35 and Ubuntu 14.04