| First Indicator | Second Indicator |
|---|---|
| Undefined # - Undefined |
151/451/551 - Undefined # - Undefined 751 - Thesaurus 0 - Library of Congress Subject Headings 1 - LC subject headings for children's literature 2 - Medical Subject Headings 3 - National Agricultural Library subject authority file 4 - Source not specified 5 - Canadian Subject Headings 6 - Répertoire de vedettes-matière 7 - Source specified in subfield $2 |
| Subfield Codes | |
|---|---|
|
Name portion
Tracing and linking subfields
|
Subject subdivision portion
|
Content designators identify the subelements occurring in geographic name headings constructed according to generally accepted cataloging and thesaurus-building conventions (e.g., Anglo-American Cataloguing Rules (AACR2), Library of Congress Subject Headings). Jurisdiction names (including those that are ecclesiastical entities) alone or followed by subject subdivisions are X51 geographic names. A corporate name, a form subheading, a title of a work, and/or a city section name entered under the name of a jurisdiction are contained in the X10 fields. Geographic names used in phrase subject headings (e.g., Iran in the Koran) are contained in the X50 fields. A geographic name that is authorized for use only as a subject subdivision part of an extended subject heading is contained in a 181 (Geographic Subdivision) field.
Only generally-applicable content designators are described in full in this section. A small number of content designators with field-specific instructions are described in the Tracings and References-General Information section (for field 451 and 551) and the 7XX Heading Linking Entries-General Information section (for field 751).
First Indicator - Undefined
Undefined and contains a blank (#).
Second Indicator
In fields 151, 451, and 551, the second indicator position is undefined and contains a blank (#). For field 751, the second indicator position contains one of the values described in the 7XX Heading Linking Entries-General Information section.
$a - Geographic name
Parenthetical qualifying information is not separately subfield coded.
| 151 | ##$aAmazon River | ||||||||
| 151 | ##$aCommunist countries | ||||||||
| 151 | ##$aHalley's comet | ||||||||
| 151 | ##$aInterstate 70 | ||||||||
| 151 | ##$aMason and Dixon's Line | ||||||||
| 151 | ##$aHimalaya Mountains | ||||||||
| 151 | ##$aIrrawaddy Division (Burma) | ||||||||
| 151 | ##$aLeesville (S.C.) | ||||||||
| 151 | ##$aPalenque Site (Mexico) | ||||||||
| 151 | ##$aPompeii (Extinct city) | ||||||||
| 151 | ##$aAltamira Cave (Spain) | ||||||||
| 151 | ##$aAntietam National Battlefield (Md.) | ||||||||
| 151 | ##$aGreenwich Village (New York, N.Y.) | ||||||||
| 151 | ##$aKing Ranch (Tex.) | ||||||||
| 151 | ##$aWarm Springs Indian Reservation (Or.) | ||||||||
| 151 | ##$aDelaware Memorial Bridge (Del. and N.J.) | ||||||||
$g - Miscellaneous information
Data element that is not more appropriately contained in another defined subfield.
| 151 | ##$aAugsburg$gRegion$xMONICA$gProjekt | ||||||||
| 151 | ##$aMichelbach$gAlzenau, Unterfranken$xApostelgarten$gLage, Weinbau [Examples in German of different types of entities with repeatable subfields $g.] |
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$i - Relationship information [451/551/751]
Designation of a relationship of the entity in a 451, 551, or 751 field to the 1XX entity in the record or a textual reference instruction phrase. For fields 451 and 551 the phrase may be system-generated from the field tag or from the codes defined for subfield $w (Control subfield). Subfield $i is appropriate only in fields 451, 551, and 751. Guidelines for using subfield $i in fields 451 and 551 are provided in the Tracings and References-General Information section. Guidelines for using subfield $i in field 751 are provided in the 7XX Heading Linking Entries-General Information section.
$v - Form subdivision
Designates a specific kind or genre of material as defined by the thesaurus being used. Subfield $v is appropriate in the X51 fields only when a form subject subdivision is added to a geographic name to form an extended subject heading.
| 151 | ##$aParis (France)$vGuidebooks | ||||||||
| 151 | ##$aRussia$xTerritorial expansion$vMaps, Pictorial | ||||||||
$w - Control subfield [451/551/751]
Codes in one or more character positions defined to control the display of information and specify relationships, restrictions, and status. Subfield $w is appropriate only in field 451, 551, and 751. Character position definitions and guidelines for applying the codes defined for subfield $w in field 451 and 551 are provided in the Tracings and References-General Information section. Character position definitions and guidelines for field 751 are provided in the 7XX Heading Linking Entries-General Information section.
$x - General subdivision
Subject subdivision that is not more appropriately contained in subfield $v (Form subdivision), subfield $y (Chronological subdivision) or subfield $z (Geographic subdivision). Subfield $x is appropriate in the X51 fields only when a topical or form subject subdivision is added to a geographic name to form an extended subject heading.
| 151 | ##$aTexas$xOfficials and employees$xPayroll deductions | ||||||||
| 151 | ##$aAix-en-Provence (France)$xSocial life and customs | ||||||||
| 151 | ##$aUnited States$xCommerce | ||||||||
$y - Chronological subdivision
Subject subdivision that represents a period of time. Subfield $y is appropriate in the X51 fields only when a chronological subject subdivision is added to a geographic name to form an extended subject heading.
| 151 | ##$aGreece$xHistory$yGeometric period, ca. 900-700 B.C. | ||||||||
| 151 | ##$aUruguay$xHistory$yGreat War, 1843-1852 | ||||||||
| 151 | ##$aUnited States$xHistory$yCivil War, 1861-1865$xConscientious objectors | ||||||||
$z - Geographic subdivision
Appropriate in the X51 fields only when a geographic subject subdivision is added to a geographic name to form an extended subject heading.
| 151 | ##$aUnited States$xBoundaries$zCanada | ||||||||
$0 - Authority record control number or standard number [551/751]
See description of this subfield in Appendix A: Control Subfields.
$1 - Real World Object URI [551/751]
See description of this subfield in Appendix A: Control Subfields.
$2 - Source of heading or term [751]
Code that identifies the source of a heading or term when the second indicator position contains value 7. Subfield $2 is appropriate only in field 751. Guidelines for applying subfield $2 are provided in the 7XX Heading Linking Entries-General Information sections.
$4 - Relationship [451/551/751]
Code or URI that specifies the relationship from the entity described in the record to the entity referenced in the field. Guidelines for using subfield $4 in fields 451 and 551 are provided in the Tracings and References-General Information section. Guidelines for using subfield $4 in field 751 are provided in the 7XX Heading Linking Entries-General Information section.
$5 - Institution to which field applies [451/551/751]
See description of this subfield in Appendix A: Control Subfields.
$6 - Linkage
See description of this subfield in Appendix A: Control Subfields.
$8 - Field link and sequence number
See description of this subfield in Appendix A: Control Subfields.
Ambiguous Headings - See Appendix D: Ambiguous Headings.
Punctuation - Punctuation of the subelements of a heading is generally dictated by descriptive cataloging or subject heading system/thesaurus rules. These input conventions clarify MARC punctuation practices. An X51 field does not end with a mark of punctuation unless the field ends with an abbreviation, an initialism, or data that ends with a mark of punctuation.
| 151 | ##$aCambridge (Mass.)$xPopulation | ||||||||
| 151 | ##$aEgypt$xHistory$yTo 332 B.C. | ||||||||
| 151 | ##$aUnited States$xEconomic policy$y1981-1993 | ||||||||
| 451 | ##$wnnaa$aChino Valley, Ariz. | ||||||||
| 151 | ##$aChina$xHistory$yHan dynasty, 202 B.C.-220 A.D.$vBibliography | ||||||||
Spacing - No spaces are used in initialisms.
| 151 | ##$aWashington (D.C.) | ||||||||
| 151 | ##$aChina$xHistory$yHan dynasty, 202 B.C.-220 A.D. | ||||||||
One space is used between preceding and succeeding initials if an abbreviation consists of more than a single letter.
| 151 | ##$aVienna (W. Va.) | ||||||||
| 151 | ##$aAdelaide Geosyncline(S. Aust.) | ||||||||
| 151 | ##$aUnited States$xForeign relations$y1993-$vPeriodicals | ||||||||
Display Constant
| - | [dash associated with the content of subfield $v, $x, $y, and $z] |
Dash (-) that precedes a subject subdivision in an extended subject heading is not carried in the MARC record. It may be system generated as a display constant associated with the content of subfield $v, $x, $y, and $z.
|
Content designated field:
|
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| 151 | ##$aUnited States$xBoundaries$zCanada | ||||||||
|
Display example: United States-Boundaries-Canada
|
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Values were: 0-9 (Number of nonfiling characters present).
City section name entered under the name of a jurisdiction is contained in an X10 field. Records created before this change may contain an X51 field with a subfield $b for this type of name.
Subfield $4 was renamed and redescribed to allow for the recording of relationship URIs in addition to MARC and non-MARC codes.