The ISIL is a variable length identifier. The ISIL consists of a maximum
of 16 characters, using digits (Arabic numerals 0 to 9), unmodified
letters from the basic Latin alphabet and the special marks solidus
(/), hyphen-minus (-) and colon (:). Latin letters modified with one
or more diacritics and letters from alphabets other than Latin
cannot be used in the ISIL. Each ISIL identifier shall be unique
when normalized to the repertoire of characters specified in
ISO/IEC-10646-1 without regard to case.
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. An ISIL is made up by two components: a
prefix and a library identifier, in that order, separated by a
hyphen-minus. The hyphen-minus is a mandatory character in the ISIL
string.
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.
| EXAMPLE 1 |
GB = United Kingdom |
| EXAMPLE 2 |
DE = Germany |
| EXAMPLE 3 |
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.
| EXAMPLE |
ZGB = Staatsbibliothek zu Berlin - Zeitschriftendatenbank |
Library identifier
The Library 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 Library 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 Library identifier will have up to 11 character positions without blanks between
country code and national identifier.