This is a help page for the Nordic libraries' URN creator provided by the "Nordic Metadata Project". The syntax of the produced URN's is authorized by the IETF URN WG and the numbering schemes are assigned by the Finnish and Swedish National Libraries.

Correct URN's can be acquired using the Dublin Core metadata template for individual documents or by getting up to 10 URN's from the separate URN creation page. However, the URN's can be used independently from Dublin Core and the metadata template.

URN USER GUIDE

Introduction

The infrastructure for global URN resolution is not yet in place, nor are the browsers adapted to interoperate with URN resolution services, which may utilise hitherto unknown protocols. Establishment of the URN resolution infrastructure will quite likely require a few years.

All URNs have the following syntax (phrases enclosed in quotes are REQUIRED):

String "urn:" in the beginning of the URN makes it possible to locate and index URN from anywhere within a document. However, it is better to place the URN not into the text part of the document, but for instance in a HTML document into the META tag of the HEAD.

NID stands for Namespace Identifier. It is a code that identifies the ID system used as URN and facilitates syntactic interpretation of the NSS, Namespace Specific String. In the URN's delivered by the national libraries through this creation tool the NID is NBN, for National Bibliography Number.

NSS is the actual code that persistently and uniquely identifies the document. The syntax of the namespace specific string may be basically anything. In a URN the NBN will always begin with country code and hyphen, followed by additional information. In Finland letters "fe", year (YY) and a number incremented with steps of one is used. An example: fi-fe976238.

An example of a complete Finnish URN: URN:NBN:fi-fe976238
A Swedish example: URN:NBN:se-d199811234

More information about URN's is available from the home page of the URN Working Group; see

http://www.ietf.org/html.charters/urn-charter.html

How to obtain an URN

URN's based on the NBN's are created by software. The URN generator is available at
http://www.lub.lu.se/dc/urntest.pl

The application is capable of delivering URN's for all Nordic countries. A user must first choose a country. the default value is set by the country code of the user's work station's Internet name; e.g. for .fi the default is Finland. Next, the user can choose the number of URN's delivered (max = 10).

The practices according to which URN's are delivered do vary a little from one country to another, but the following principles do generally apply everywhere:

1. It is recommended that URN's are only acquired for documents which are reasonably stable and which do have a significant information content.

2. Copies of the same document shall all use the same URN (this document has one URN but several URL's).

3. Versions of a resource in different file formats (e.g. a text file in MS Word and HTML) should all have their own URN's. In order to improve searchability, the source document's URN's should be put into the metadata embedded in the derived documents (see below).

4. When the document is being edited, a new URN is needed only when there are changes in the intellectual content. Editorial changes like fixes to typing errors do not make it necessary to obtain a new URN.

5. If a network document already has an ISBN, ISSN or an another ID, it can be used as an URN. NID's for traditional ID systems have not yet been decided, but it is quite likely that NID for ISBN will be "ISBN", for ISSN "ISSN" and so forth. Examples:
   URN:ISBN:<ISBN-number> URN:ISSN:<ISSN-number>

   As a main rule, regular publishers should use URN's in compliance with their profession's established identification systems (e.g. ISBN, BICI, ISSN, SICI). As an alternative to URN these publishers may use DOI (Digital Object Identifier, see http://www.doi.org/).

6. A document should have only one URN. However, if a document consists of several individual files, these should be identified separately.

How to put URN's into documents

Example:

If you have many versions of the same document in different formats, they all need an URN. To enable users to find the original (source) version, you should put it's URN into the metadata of derived records. Use Dublin Core Source tag for the source ID. Example:

Creating Dublin Core metadata manually is a complex task. The job can be made a lot easier with a metadata template, which automatizes creation of DC syntax. Such a template, developed in the Nordic Metadata Project, is available at

http://www.lub.lu.se/cgi-bin/nmdc.pl

How will the URN be used

The browsers are at the moment not capable to find the document when you put the URN into the Location: box. This is because an international URN resolution infrastructure is not in place yet. If you include the URN into the body text of your document, most major search services will be able to retrieve the document in one or the other way, mostly among other hits. Included into the HTML Head's META tag, the URN will be found only by the very few search services which index such a META tag at the moment. To be future proof and to be found in Nordic Indexes we recommend strongly to provide the URN in the META tag of your document as well.

In the future the Nordic Web Index (NWI) system's national full-text and metadata databases (see for instance Swemeta at http://nwi.ub2.lu.se/?lang=en will offer you the full and correct searchability of all URN's used in WWW documents published in the respective countries. In those databases you will always be able to look up URN's from these countries. The robots collecting information for those databases will normally find your document after it is published on the net. If you use our DC Metadata creator you can be sure that your document and all metadata connected to it, incl. the URN, will be indexed correctly a few days later.

When URN's are used on a broader scale, you can expect most search services to be able to find your URN. The URN's we are providing now are authorized and will always be valid. The final step in this development will be that URN's replace the URL's when you are looking for a document and will click on them and put them into "Location" boxes as you do now with URL's. The big difference will be, that URN's will always give you the right document independent of its actual location. In some cases this will be accomplished using WWW archives like the Swedish Kulturarw3 and the Finnish EVA.?

Frequently Asked Questions

• 1. I am a publisher, having used a couple of ISBN's already, but don't want to use DOI's for my books.
• 2. Do I need a URN for the original publication and the digitized form?

        DC Metadata Template      URN Creator