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MARC PROPOSAL NO. 2022-04

DATE: December 21, 2021
REVISED:

NAME: Recording Representative Expressions in the MARC 21 Authority and Bibliographic Formats

SOURCE: MARC/RDA Working Group

SUMMARY: This proposal discusses the potential for encoding representative expressions in the MARC 21 Formats using a new Field 387 with exceptions for music specific elements.

KEYWORDS: Expression (AD, BD); Field 387 (AD, BD); Representative Expressions (AD, BD); Field 382, 1st indicator (AD, BD); Medium of Performance (AD, BD); Field 384, 1st indicator (AD, BD); Key (AD, BD); RDA Toolkit Restructure and Redesign Project; RDA

RELATED: 2021-DP12

STATUS/COMMENTS:
12/21/21 – Made available to the MARC community for discussion.

01/26/22 – Results of MARC Advisory Committee discussion: Approved, with one amendment: the 387 field label will be changed to “Representative Expression Characteristics”. A Fast-Track proposal may be submitted to the MARC Steering Group for changing the repeatability of field 384 in the Authority format so that both a key of expression and key of representative expression can be recorded in the same record.

05/17/22 – Results of MARC Steering Group review - Agreed with the MAC decision.

Proposal No. 2022-04: Recording Representative Expressions

1. BACKGROUND

The new RDA Toolkit glossary defines a representative expression as: "An expression that is considered a canonical source of data for identifying a work." Various elements belonging to the work and expression entities, as scoped by RDA, can already be recorded in the MARC 21 formats. However, information which designates representative expressions cannot, for the most part, be described in an unambiguous and granular way. This paper examines the scope for recording representative expression elements within MARC 21 and the practical benefits for doing so. It goes on to make a case for expanding MARC 21's accommodation of representative expressions using the combination of a new field 387 (Representative Expressions) and new indicator values in existing fields 382 (Medium of Performance) and 384 (Key). RDA does not make the recording of representative expression information a required aspect of resource description; the community may choose to do so within the context of an application profile.

2. DISCUSSION

2.1. Representative expressions and the practical benefits of identifying them

The new RDA Toolkit introduces a set of elements with which to record various attributes of representative expressions. By doing so it reflects RDA's wider goal of implementing the IFLA Library Reference Model. Providing context, the new Toolkit's guidance chapter on representative expressions notes the following:

"The IFLA library reference model treats as equal all expressions that realize a work. However, certain characteristics of an expression are considered to best represent the intention of the creators of the work. A representative expression that has these characteristics may be assumed to be an original or canonical realization of the work. Manifestations that embody representative expressions may be the specific target of a search using RDA data. There may be two or more expressions that can be treated as a representative expression of a work, and an expression does not need to be extant to be a representative expression."

Enabling a catalog user to identify the representative expression of a work in an unambiguous and granular way could be beneficial in terms of refining their search strategy. It would mean that they could more easily pinpoint the expression over which an author, composer, director, etc. is considered to have exercised the most creative control. Other expressions which arose from translation, technical limitations, editorial amendments, etc. could be filtered out as a consequence. Recording information which pertains to representative expressions could also be of service to the bibliographic researcher interested in tracing the history of a work's development over time and how alternative expressions may have diverged from the creator's original intent. In circumstances where the representative expression of a work is not apparent, then a given community may default to designating the earliest available expression as representative (e.g., a manifestation of that expression which contains the original publication date). In cases where different expressions of a work are manifested simultaneously, agencies may determine criteria for picking a value from one of those expressions or use values from multiple expressions if determined to be representative (e.g., one which corresponds to the language of a catalog). A community may choose not to identify representative expressions in the context of its cataloging activities, or only to do so selectively.

2.2. Describing representative expressions in a current MARC 21 context

The canonical version of a resource may already be described in a MARC 21 record context. This sometimes occurs as unstructured information which is transcribed from the resource itself. The following example is given for illustration:

500 $a “The composer … participated in the editing process. Thus each work can be considered a ‘definitive’ version, authorized and approved by Harrison”---P.153

Alternatively, such information may be recorded as part of a structured description. The following example is given for illustration:

381 $a Final cut $a 25th anniversary edition $a 2007 final cut $a Definitive version $a 2007 version

Although both of these approaches express the concept of a canonical version, in each case the coding conflates this information with other, separate aspects of resource description. While the designation of a canonical version may be discernible to a human reader in each case, it would be less easily subject to machine interpretation. As a result, existing coding could not be expected to support the customized indexing or faceting of search results. Nor would it support linked data applications.

Besides the challenges of conflation set out above, it is also noteworthy that, at present, MARC 21 coding does not generally allow for distinctions to be made between the different characteristics of canonical versions. The new RDA Toolkit defines twenty-two elements which can be used for this purpose.

Eight are reciprocal relationship elements:

• representative expression
• representative expression of
• date of representative expression
• date of representative expression of
• date of capture of representative expression
• date of capture of representative expression of
• place of capture of representative expression
• place of capture of representative expression of

Fourteen additional elements are not reciprocal relationships:

• aspect ratio of representative expression
• color content of representative expression
• content type of representative expression
• duration of representative expression
• extent of representative expression
• intended audience of representative expression
• key of representative expression
• language of representative expression
• medium of performance of choreographic content of representative expression
• medium of performance of musical content of representative expression
• projection of cartographic content of representative expression
• scale of representative expression
• script of representative expression
• sound content of representative expression

As regards the relationship elements listed above, "representative expression" and its reciprocal "representative expression of", could already be recorded using instances of subfield $i (Relationship information) in the MARC 21 Authority and Bibliographic Formats.

The following example illustrates an application in the Authority format:

100 1# $ a Mann, Thomas, $d 1875-1955. $t Tonio Kröger
500 1# $ w r $i representative expression: $ a Mann, Thomas, $d 1875-1955. $t Tonio Kröger $l German

The following example illustrates an application in the Bibliographic format:

245 10 $a Étude macabre.
500 ## $a For piano (left hand)
700 1# $i representative expression of : $a Godowsky, Leopold, $d 1870-1938.
       $t Etude macabre $4 http://rdaregistry.info/Elements/e/P20325 
       $1 http://viaf.org/viaf/186595821

The relationship "place of capture of representative expression" and its reciprocal could equally be recorded using appropriate coding in the Authority format 5XX (See Also From Tracings) when combined with subfield $i. Likewise, recording relationships for "date of representative expression", "date of capture of  representative expression" and their reciprocals could be undertaken in an authority context. In the Bibliographic format, 7XX (Linking Entries) could be combined with subfield $e to record "place of capture of representative expression". However, in this  format there is currently no means for establishing a reciprocal. Nor can a relationship be recorded between a work and a timespan using a 7XX field for the elements "date of representative expression", "date of capture of representative expression" and their reciprocals. Field 388 (Time Period of Creation) may be used to record a controlled value for a timespan, but neither subfields $i nor $e are currently defined to carry a relationship there.

Besides the options which it provides for recording relationships, the MARC 21 Authority format  offers a means of flagging representative expression characteristics using field 075 (Type of Entity). The following example illustrates an application in the context of the element "key of representative expression". The presence of the value "Work" in field 075 could be used to indicate that the contents of field 384 (Key) is a value of the work element "key of representative expression", not a value of the expression element "key of expression".

075 ## $a Work
100 1# $a Beethoven, Ludwig van, $d 1770-1827. $t Allemande, $m piano, $n WoO 81, $r A major
384 0# $a A major $1 http://www.wikidata.org/entity/Q277793

There is currently no means to flag representative expression characteristics in the same way using the Bibliographic format, since the 075 field is not defined there. However, it is also noteworthy that the Authority format currently does not provide a means of unambiguously recording the following expression characteristics which might otherwise be contextualized as representative expression information by using the 075:

• aspect ratio
• color content
• duration
• extent of expression
• medium of performance of choreographic content of expression
• projection of cartographic content of expression
• scale
• script
• sound content

Field 381 (Other Distinguishing Characteristics of Work or Expression) might be used to record values for the above in the Authority format but, as previously noted, this field lacks the machine actionability which more specific coding would provide.

The following table offers an overview of current coding for the purpose of recording representative expression elements as relationships in the MARC21 Formats:

Table 1

The following table offers an overview of coding which is already available for the purpose of recording other representative expression elements in the MARC 21 Authority Format in combination with field 075; where gaps occur, coding for the equivalent expression element in the Bibliographic format is provided (if available):

Table 2

The following table offers an overview of the coding which is already available to record  the elements date of capture, date of expression and place of capture in cases where it is not used to establish reciprocal relationships between records in the Authority format. Where gaps occur, coding for the equivalent expression element in the Bibliographic format is provided:

Table 3

2.3. Community Feedback and Preferences Regarding the Expanded Coverage of Representative Expressions in MARC 21

The case made by discussion paper 2021-DP12 for expanding MARC 21’s current accommodation of representative expression information met with general approval from the MARC 21 community. There was a recognition of the need to provide a solution which encompassed both the Authority and Bibliographic formats. There was also an acceptance of the need to consider coding solutions for the new RDA elements "extent of expression" and "medium of performance of choreographic content", before making decisions about their representative expression counterparts.

The options put forward by the discussion paper to better accommodate other representative expression elements gained varying degrees of support. The option to add expression level coding to the Authority format and then use it in combination with field 075 (Type of Entity) in order to designate representative expression data was considered workable, but one which did not allow for applications in the Bibliographic format. The option to define field 075 (Type of Entity) in the Bibliographic format was considered unworkable, because it would require the use of subfield $8 (Field link and sequence number) to distinguish representative expression as opposed to manifestation and item level information. The option to expand the coverage of field 381 (Other Distinguishing Characteristics of Work or Expression) in both formats to designate representative expressions was considered too clumsy. It would require a broadening of the existing field's definition and scope. It would also not allow for the entry of coordinated data strings in a way which is currently supported by field 382 (Medium of Performance). The options to define a new field 387 (Representative Expressions) in the formats, to introduce new indicator coding in existing fields, or to use a combination of these last two options met with greater approval in a series of straw polls which were conducted at the latest MAC meetings.     

Of the MARC 21 communities canvassed at MAC, only the Music Library Association has expressed a strong preference that indicator values be used in existing fields to designate representative expression information. Hitherto, MLA's approach to medium of performance information has required that a term be accompanied by a numerical value when recording this element.

Example:

382 01 $a violin $n 1$p flute $n1 $a cello $n 1 $a piano $n 1 $s 3 $2 lcmpt
[A work for violin or flute, cello, and piano.]

MLA argues that if the element "medium of performance of musical content of representative expression" were to be recorded in a new 387 field without the number of performers associated with it, then valuable contextualizing information would be lost as a result. It further contends that, if an indicator based solution is adopted in this case, then a similar approach should be taken to recording the element "key of representative expression" : i.e., this should be done using the existing field 384 (Key) rather than a new 387. In this way both types of music specific coding could be treated consistently.

Unlike MLA, other MARC 21 communities have not set out specific use cases for recording representative expression information in existing fields. However, a number including the U.K., Canada, Germany, Spain, NLM and PCC have noted the potential for using a new field to record this information. An advantage of using field 387  would be consistent coding for representative expression information (with the exceptions for music noted above as regards fields 382 and 384). Such consistency may be less easily achieved if one uses indicators in existing fields.  Excluding fields 382 and 384, of the existing fields listed in table 2 and 3 above, some already contain indicator values, while others do not.

The following table indicates indicator coverage in the Authority format:

Table 4

The following table indicates indicator coverage in the Bibliographic format:

Table 5

Additional indicator values might be defined which supplement those already present in fields 033 and 034 in the Authority format and in fields 033, 034, 046, 377 and 521 in the Bibliographic format. However, this approach may require that the scope of existing indicators needs to be broadened. Alternatively, indicator 1 or indicator 2 might be used in cases where the other indicator present in a field is already defined. However, this would lead to additional inconsistency beyond the exceptions already noted for music.

3. PROPOSED CHANGES

3.1. Define New Field 387

In the MARC 21 Authority and Bibliographic formats define new field 387 as follows:

387 – Representative Expressions (R)

FIELD DEFINITION AND SCOPE
A characteristic of an expression that is considered a canonical source of data for identifying a work.

INDICATORS
Both indicator positions are undefined; each contains a blank (#).

SUBFIELD CODES

$a - Aspect ratio of representative expression (R)
A numerical ratio of the width to the height of a representative expression of a moving image work.

$b - Color content of representative expression (R)
An indication of the presence of color or tone in the content of a representative expression of a work.

$c - Content type of representative expression (R)
A categorization of a representative expression that reflects the fundamental form of communication in which the content is expressed and the human sense through which it is intended to be perceived.

$d - Date of capture of representative expression (R)
A timespan that is associated with recording, filming, etc., the content of a representative expression.

$e - Date of representative expression (R)
A timespan that is the earliest associated with a representative expression of a work.

$f - Duration of representative expression (R)
An extent of expression of a representative expression of a work that is a playing time, performance time, running time, or other length of time.

$g -  Intended audience of representative expression (R)
A category of user for whom a representative expression of a work is intended, or for whom a representative expression of a work is considered suitable.

$h -  Language of representative expression (R)
A language used for the content of a representative expression of a work.

$i - Place of capture of representative expression (R)      
A place that is associated with recording, filming, etc., the content of a representative expression.

$j - Projection of cartographic content of representative expression (R)
A method or system used to represent the surface of the earth or of a celestial sphere on a plane in a representative expression of a work.

$k - Scale of representative expression (R)
A ratio of the dimensions of a representative expression of an image or three-dimensional form to the dimensions of the thing that is represented.

$l - Script of representative expression (R)
A set of characters or symbols used to express written language content of a representative expression of a work.

$m - Sound content of representative expression (R)
A presence or absence of sound in a representative expression of a work.

$0 - Authority record control number or standard number (R)
See description of this subfield in Appendix A: Control Subfields.

$1 - Real World Object URI (R)
See description of this subfield in Appendix A: Control Subfields.

$2 - Source of term (NR)
MARC code that identifies the source of the term or code used to record the representative expression information.

$3 - Materials specified (NR)
Part of the described materials to which the field applies.

$6 - Linkage (NR)
See description of this subfield in Appendix A: Control Subfields.

$8 - Field link and sequence number (R)
See description of this subfield in Appendix A: Control Subfields.

3.2. Define New First Indicator Values in Field 382

In field 382 (Medium of Performance) of the MARC 21 Authority and Bibliographic Formats, define new first indicator values "2" and "3" as follows:

First Indicator - Display constant controller

# - No information provided

0 - Medium of performance
The complete medium of performance of the musical work/expression.

1 - Partial medium of performance
Incomplete medium of performance of the musical work/expression. To be used when certain instruments or voices are prominent but the complete instrumentation is unknown to the cataloger.

2 - Medium of performance of musical content of representative expression
An instrument, voice, or ensemble used, or intended to be used, for performance of musical content of a representative expression of a work.

3 - Partial medium of performance of musical content of representative expression
Incomplete medium of performance of musical content of representative expression of a work. To be used when certain instruments or voices are prominent but the complete instrumentation is unknown to the cataloger.

3.3. Define New First Indicator Value in Field 384

In field 384 (Key) of the MARC 21 Authority and Bibliographic Formats, define new first indicator value "2" as follows:

First Indicator - Key type

# - Relationship to original unknown
The relationship of the specified key to the original key in which the musical composition was written.

0 - Original key

1 - Transposed key
A different key from that of the original work.

2 – Key of representative expression
Key for performance of musical content of a representative expression of a work.

4. EXAMPLES

The examples given below model the approaches to coding representative expression information which have been set out in the proposal. In each case the MARC format, element and recording method is noted for context.

4.1.

100 2#    $a Tomasi di Lampedusa, Giuseppe, $d 1896-1957.
245 13    $a Il gattopardo / $c Giuseppe Tomasi di Lampedusa.
250        $a Ed. speciale.
260        $a Milano : $b Club degli editori, $c c1969.
300 ##    $a xi, 261 p. ; $c 21 cm.
387 ##    $e 1969 
500         $a Originally published: Feltrinelli, c1958.

Format : Bibliographic
Element : Date of representative expression
Recording method : Structured

4.2.

130  0#  $a Once upon a time in America (Motion picture)
245 10   $a Once upon a time in America / $c The Ladd Company ; Warner Bros. ; Embassy International Pictures ; Empax Films ; directed by Sergio Leone ; produced by Arnon Milchan ; screenplay by Leonardo Benvenuti, Piero De Bernardi, Enrico Medioli, Franco Arcalli, Franco Ferrini, Sergio Leone.
250        $a [Long version]
260 ##   $a United States : $b The Ladd Company : $b Warner Bros., $c  1985.
300 ##   $3 viewing print. $a 24 film reels of 24 on 12 (ca. 226 min., ca. 20,340 ft.): $b sd., col. ; $c 35 mm.
387 ##   $f 034600   
500 ##   $a The shortened edited version of this film was released in 1984. Per M/B/RS descriptions file (New York times, 10-22-1992), the long version (also called "director's cut") has been shown sporadically at movie houses, is available on home video and was also released theatrically in 1991. LC also holds the shortened edited version of this film.

Format : Bibliographic
Element : Duration of representative expression
Recording method : Structured

4.3.

245 02    $a A new Mapp of the Kingdome of England, Representing the Princedome of Wales, and other Provinces, ... with the Roads from Town to Town ... Printed and given out at Amsteldam by Nicolas Visscher ... and are to be sould at London by John Overton ...
255 ##    $a Scale 1: 1 200 000.
387 ##    $k Scale 1: 1 200 000.
264 1#    $c [1685?]
300 ##    $c 75 x 58 cm
700 1#    $a Overton, John, $d 1640-1708?.
700 1#    $a VISSCHER, Nicolaes, $c 1618-79, called Piscator.

Format : Bibliographic
Element : Scale of representative expression
Recording method : Structured

4.4.

100 1# $a Walckiers, Eugène, $d 1793-1866.$t Trios, $m piano, flute, cello, $n op. 97, $r D minor
382 2# $a piano $n 1 $a flute $n 1$a cello $n 1 $s 3 $2 lcmpt
670 ## $a Trio en re mineur pour piano, flute et violoncelle, op. 97, [ca. 1859], ©2009: $b cover (Trio op. 97 d-moll für Flöte, Violoncello und Klavier)

Format : Authority
Element : Medium of performance of musical content of representative expression
Recording method : Structured

4.5.

100 1# $a Schumann, Robert, $d 1810-1856. $t Albumblätter, $m piano, $n op. 124. $p Wiegenliedchen
384 2# $a G major $1 http://www.wikidata.org/entity/Q5728362

Format : Authority
Element : Key of representative expression
Recording methods : Structured and Internationalized Resource Identifier (IRI)

5. BIBFRAME DISCUSSION

When specific changes are further developed, approved, and implemented the BIBFRAME conversions can be modified if necessary.

6. SUMMARY OF PROPOSED CHANGES

In the MARC 21 Authority and Bibliographic Formats:

6.1. Define new field 387 (Representative Expressions) as follows (see full description of the field in Section 3.1.):

• 387 - Representative Expressions (R)
  • 
    Indicators
    • First - Undefined
      • # - Undefined
    • Second - Unedefined
      • # - Undefined
        
  • Subfield Codes
    • $a - Aspect ratio of representative expression (R)
    • $b - Color content of representative expression (R)
    • $c - Content type of representative expression (R)
    • $d - Date of capture of representative expression (R)
    • $e - Date of representative expression (R)
    • $f - Duration of representative expression (R)
    • $g - Intended audience of representative expression (R)
    • $h - Language of representative expression (R)
    • $i - Place of capture of representative expression (R)
    • $j - Projection of cartographic content of representative expression (R)
    • $k - Scale of representative expression (R)
    • $l - Script of representative expression (R)
    • $m - Sound content of representative expression (R)
    • $0 - Authority record control number or standard number (R)
    • $1 - Real World Object URI (R)
    • $2 - Source of term (NR)
    • $3 - Materials specified (NR)
    • $6 - Linkage (NR)
    • $8 - Field link and sequence number (R)

6.2. Define new first indicator values "2 - Medium of performance of musical content of representative expression" and "3 - Partial medium of performance of musical content of representative expression" in field 382 (Medium of Performance), as described in Section 3.2.

6.3. Define new first indicator value "2 - Key of representative expression" in field 384 (Key), as described in Section 3.3.

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