This page is obsolete. For up-to-date guidelines please see our
DOI Display Guidelines page. Basic DOI Syntax A Digital Object
Identifier (DOI), is a unique string created to identify a piece
of intellectual property in an online environment. Detailed
information about the DOI itself can be found in the DOI
Handbook at http://www.doi.org/hb.html. For the purpose of
assigning DOIs and registering them with CrossRef, you need only
familiarize yourself with the contents of this brief document.
The DOI is made up of two components, a prefix and a suffix,
separated by a forward slash. See figure 1. All DOI prefixes
begin with "10" to distinguish the DOI from other
implementations of the Handle System followed by a four-digit
number or string (the prefix can be longer if necessary). In
general each member has one prefix, but it is possible for
members to have multiple prefixes (e.g. a prefix for each
journal title). The suffix is determined by the publisher -- see
the section below on creating a DOI suffix scheme.