An ISIL is made up by two components: a
prefix and a unit identifier, in that order, separated by a
hyphen-minus. The hyphen-minus is a mandatory character in the ISIL
Country code prefix
A country code identifies the country in which the library or related
organization is located at the time the ISIL is assigned. The country
code shall consist of two uppercase letters in accordance with the
codes specified in ISO 3166-1. All two-character alphabetic
combinations are reserved for possible future assignment as
country codes, thus may not be assigned as non-country code prefixes.
||GB = United Kingdom
||DE = Germany
||SE = Sweden
When the library has components located in different geographic areas,
the country code is based on the location of the main library or of the
main administrative unit.
Non-country code prefixes
A non-country code prefix is any combination of Latin alphabet
characters (upper or lower case) or digits (but not special marks).
The prefix may be one, three, or four characters in length. The prefix
is registered at a global level with the ISIL Registration Authority.
||ZDB = Staatsbibliothek zu Berlin - Zeitschriftendatenbank
The Unit identifier is an alphanumeric element designed to
accommodate existing national systems of library identification or
newly assigned identifiers for libraries or related organizations.
Already existing identifiers, when used in international contexts,
will necessarily require the addition of the two uppercase letters
of the respective country code, followed by a hyphen-minus character.
If appropriate when assigning a new identifier to a library or
related organization, it is recommended that the Unit identifier
of the ISIL include the element indicating the geographic subdivision
(state, province, region, city, etc.) where the library or the related
organization is located. If the geographic subdivision element is used,
it is recommended that the element be in accordance with the codes
specified in ISO 3166-2.
The Unit identifier will have up to 11 character positions.
When an ISIL is written, printed, or otherwise visually presented, it shall
be preceded by the letters ISIL separated from the identifier by a space.
ISO 15511 does not specify any restrictions on how data defining an ISIL is
to be stored in a computer system (including RFID-tags).
So the hyphen between
prefix and identifier don't need to be stored at a RFID-tag.
The crucial point is the presentation for human beings. This must be the text
ISIL, a speace, the prefix, a hyphen and the identifer:
Illustration: ISIL DK-710100
Even though an ISIL shall be unique with regards to case, the presenation shall be
with upper or lower case as showed at the Registration Allocation Agency list or