Bibliographies and DOI numbers

Some bibliography entries are produced with a Digital Object Identifier (DOI).  This is a filename code that identifies a text on-line.  In order to download a DOI datafile you will need to log on to a DOI website such as;

The code number can then be used to locate a data copy of the document by entering the DOI code into the site.  An example of a DOI code format is shown here;

DOI:     10.4202/app.2010.0079

This will call up a website download page that will usually display the text title and abstract.  Many documents are subject to copyright and you may require a membership or subscription to the site to view the complete document.  The given example document is held at Acta Palaeotologica Polonica;
In this case, the document is available in .pdf format if you click on the link, lower left on the page displayed by the DOI link.

Elgin, R.A. and Frey, E. 2012. A nearly complete ornithocheirid pterosaur from the Aptian (Early Cretaceous) Crato Formation of NE Brazil. Acta Palaeontologica Polonica 57 (1): 101–110.  DOI: 10.4202/app.2010.0079