1. General information about ISSN
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The International Standard Serial Number is an 8-digit code used to identify unambiguously newspapers, journals, magazines and periodicals of all kinds and on all media–print and digital.

The ISSN can be thought of as the social security number of the serials world. Just as an individual's social security number is used in many automated systems to distinguish that person from others with the same or similar names, the ISSN distinguishes a particular serial from others with which it might be mistaken.

- Publishers who wish to identify their serial publications and incorporate a barcode on the magazine, journal or newspaper for sale via major retailers.

- Libraries that use the ISSN as a fundamental identifier for distinguishing between identical serial titles and facilitating checking and ordering procedures, collection management, legal deposit, digital preservation, interlibrary loans, etc.

- Catalogue databases that use the ISSN as a record control number and can make use of the records from the ISSN register.

- Documentation centres and databases that handle bibliographic references and use the ISSN for more accurate serials citation, abstracting and indexing services, etc.

- Subscription agencies which act as intermediaries between publishers and their customers, use the ISSN to ensure the correct serial publication is delivered.

- Academics who wish to cite publications with full details for research purposes.

- Retailers / wholesalers that use ISSN-based barcodes within their own internal systems in order to assess and control magazine/newspaper circulation.

Publications that are issued over time with no predetermined conclusion, whether print or digital (online resource, application for mobile device, CD-ROM for instance): serials (journals, newspapers, magazines, monographic series...), ongoing integrating resource(s) (websites, databases...).

The ISSN identifiers are assigned at the request of publishers or third parties. ISSN are assigned either by ISSN National Centres for resources handled by publishers located in their respective countries or by the ISSN International Centre for publishers based in countries without a National Centre, for international organizations, or for multinational publishers having a specific agreement with the ISSN International Centre [see section 8. You are a publisher, or a third party requesting an ISSN assignment]. The ISSN International Centre and the 89 ISSN National Centres form together the ISSN Network.

When a serial is available in more than one physical format and a separate ISSN has been assigned to each format, the ISSN Network designates a linking ISSN (ISSN-L) from one of these ISSN. The ISSN-L is available for use when there is a need to identify and link to a continuing resource without regard to format, for example in services such as OpenURL, library catalogues, search engines or knowledge bases.

Books (monographs) published within a series and annual / biennial publications are eligible for both ISBN and ISSN assignment.

An ISBN identifies an individual book in a series, or a specific year for an annual or biennial, and a different ISBN is used for every book.

An ISSN identifies the title of the monographic series, or the ongoing annual or biennial, and the same ISSN is displayed on every book published within that series as long as the series title remains unchanged. The series title must be clearly and explicitly stated on each book, for example, on the front or back cover, on the title page, or on the editorial page, in order to be eligible for an ISSN.

No, unlike the ISBN code, which contains country and publisher prefixes, an ISSN is an opaque identifier associated with a serial title, containing no information as to the publisher or its location.

No, the ISSN is not related to ownership of a journal and does not confer copyright. A new ISSN will be required if the change of publisher results in a change of the serial title.

ISSN is assigned to a specific title. A new ISSN is usually needed if a title changes.

Separate ISSN are needed for serials published in different physical formats. If your printed serial already has an ISSN and an online version is being produced for the first time, the online version is considered to be a new serial.

If a publication is being relaunched with the same title, then the existing ISSN is still valid for use, even if there has been a publishing gap. No new ISSN should be assigned in this circumstance. If a serial reverts to a title that it held previously, a new ISSN needs to be assigned. The publisher cannot revert to using the previous ISSN.