The FRBR Model

Every Akoma Ntoso document is identified using the FRBR model (Functional Requirements for Bibliographic Records). FRBR distinguishes four abstraction levels for any document, which is essential for legal texts because laws evolve through versions, translations, and formats.

The four levels

Work            "The Constitution of Country X"           (the abstract concept)
  └─ Expression    "...as amended on 2024-01-15, in English"  (a specific version + language)
       └─ Manifestation  "...in XML format"                        (a specific file format)
            └─ Item          "...stored at this URL"                    (a specific copy)

Work

The Work is the abstract intellectual creation. It is the law itself — not any particular text of it, but the concept.

• "The Civil Code of France" is a Work
• "Act 3 of 2015" is a Work
• A Work has no text — it's an identifier for the thing that all versions refer to

In AKN XML: <FRBRWork> inside <identification>.

Expression

An Expression is a specific realization of a Work: a particular version, in a particular language, at a particular point in time.

• "The Civil Code of France, as consolidated on 2024-01-01, in French" is an Expression
• "Act 3 of 2015, as originally enacted, in English" is an Expression
• Every time a law is amended, a new Expression is created

In AKN XML: <FRBRExpression> inside <identification>.

Manifestation

A Manifestation is the physical or digital embodiment of an Expression.

• The XML file of that version is a Manifestation
• The PDF published in the official gazette is a Manifestation
• The HTML rendering on the parliament's website is a Manifestation
• All Manifestations of the same Expression have the same textual content, just in different formats

In AKN XML: <FRBRManifestation> inside <identification>.

Item

An Item is a specific physical copy of a Manifestation. This level is rarely relevant for digital documents but exists for completeness (e.g., "the copy of the official gazette in this library").

AKN does not require Item-level identification.

How it maps in XML

Every AKN document has an <identification> block in its <meta> section with all three levels:

<meta>
  <identification source="#author">
    <FRBRWork>
      <FRBRthis value="/akn/sl/act/2004-02-13/2"/>
      <FRBRuri value="/akn/sl/act/2004-02-13/2"/>
      <FRBRdate date="2004-02-13" name="enactment"/>
      <FRBRauthor href="/akn/ontology/person/sl.parliament"/>
      <FRBRcountry value="sl"/>
    </FRBRWork>
    <FRBRExpression>
      <FRBRthis value="/akn/sl/act/2004-02-13/2/eng@2004-07-21"/>
      <FRBRuri value="/akn/sl/act/2004-02-13/2/eng@2004-07-21"/>
      <FRBRdate date="2004-07-21" name="amendment"/>
      <FRBRlanguage language="eng"/>
    </FRBRExpression>
    <FRBRManifestation>
      <FRBRthis value="/akn/sl/act/2004-02-13/2/eng@2004-07-21/main.xml"/>
      <FRBRformat value="application/akn+xml"/>
    </FRBRManifestation>
  </identification>
</meta>

Key elements

URI construction basics

The FRBR levels build upon each other in the URI:

Work:           /akn/sl/act/2004-02-13/2
Expression:     /akn/sl/act/2004-02-13/2/eng@2004-07-21
Manifestation:  /akn/sl/act/2004-02-13/2/eng@2004-07-21/main.xml

For full URI construction rules, see Naming convention.

Why this matters

The FRBR model solves a real problem: when a legislator says "Article 5 of Act 3," they might mean:

• Article 5 as it exists today
• Article 5 as it was when first enacted
• Article 5 as it was on a specific date
• Article 5 in French vs. English

FRBR gives each of these a distinct, unambiguous identity. This is essential for cross-references, amendment tracking, and consolidated law databases.

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