„Authority 045” változatai közötti eltérés

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(10 közbenső módosítás ugyanattól a szerkesztőtől nincs mutatva)
8. sor: 8. sor:
 
== First Indicator ==
 
== First Indicator ==
  
Type of time period in subfield $b or $c
+
:''Type of time period in subfield $b or $c''
# - Subfield $b or $c not present
+
:'#' - Subfield $b or $c not present
0 - Single date/time
+
:0 - Single date/time
1 - Multiple single dates/times
+
:1 - Multiple single dates/times
2 - Range of dates/times
+
:2 - Range of dates/times
  
 
 
 
== Second Indicator ==
 
== Second Indicator ==
  
Undefined
+
:''Undefined''
# - Undefined
+
:'#' - Undefined
  
 
 
24. sor: 24. sor:
 
== Subfield Codes ==
 
== Subfield Codes ==
  
$a - Time period code (R)
+
:$a - Time period code (R)
$b - Formatted 9999 B.C. through C.E. time period (R)
+
:$b - Formatted 9999 B.C. through C.E. time period (R)
$c - Formatted pre-9999 B.C. time period (R)
+
:$c - Formatted pre-9999 B.C. time period (R)
$6 - Linkage (NR)
+
:$6 - Linkage (NR)
$8 - Field link and sequence number (R)
+
:$8 - Field link and sequence number (R)
  
 
== FIELD DEFINITION AND SCOPE ==
 
== FIELD DEFINITION AND SCOPE ==
  
  
Time period code (subfield $a) and/or a formatted time period (subfield $b or $c) associated with a 15X heading in an established heading record or a 18X heading in a subdivision record.
+
:Time period code (subfield $a) and/or a formatted time period (subfield $b or $c) associated with a 15X heading in an established heading record or a 18X heading in a subdivision record.
  
Time period code in subfield $a is derived from the B.C. (Before Common Era) and/or C.E. (Common Era) lists in the Time Period Code Table provided under the description of subfield $a.
+
:Time period code in subfield $a is derived from the B.C. (Before Common Era) and/or C.E. (Common Era) lists in the Time Period Code Table provided under the description of subfield $a.
  
 
== GUIDELINES FOR APPLYING CONTENT DESIGNATORS ==
 
== GUIDELINES FOR APPLYING CONTENT DESIGNATORS ==
  
INDICATORS
+
:'''INDICATORS'''
First Indicator - Type of time period in subfield $b or $c
+
 
Whether a subfield $b or $c is present in the field; and, when subfield $b or $c is present, the type of time period it contains. The values distinguish among a single date/time, multiple single dates/times, and a range of dates/times.
+
:'''First Indicator - Type of time period in subfield $b or $c'''
# - Subfield $b or $c not present
+
::Whether a subfield $b or $c is present in the field; and, when subfield $b or $c is present, the type of time period it contains. The values distinguish among a single date/time, multiple single dates/times, and a range of dates/times.
0 - Single date/time
+
 
Subfield $b and/or $c is present and contains a single date/time.
+
:::'#' - '''Subfield $b or $c not present'''
 +
 
 +
:::'''0 - Single date/time'''
 +
::::Subfield $b and/or $c is present and contains a single date/time.
 
 
150 ##$aLunar petrology
+
:::::150 ##$aLunar petrology
045 0#$c2500000000
+
:::::'''045''' 0#$c2500000000
1 - Multiple single dates/times
+
 
Multiple $b and/or $c subfields are present, each containing a date/time. A range of dates/times is identified by value 2.
+
:::'''1 - Multiple single dates/times'''
 +
::::Multiple $b and/or $c subfields are present, each containing a date/time. A range of dates/times is identified by value 2.
 
 
045 1#$bd1972$bd1975
+
:::::'''045''' 1#$bd1972$bd1975
[1972 and 1975]
+
::::::''[1972 and 1975]''
2 - Range of dates/times
+
 
Two $b and/or $c subfields are present and together express a range of dates and/or times. Multiple single dates and/or times are identified by value 1.
+
:::'''2 - Range of dates/times'''
 +
::::Two $b and/or $c subfields are present and together express a range of dates and/or times. Multiple single dates and/or times are identified by value 1.
 
 
150 ##$aShenandoah Valley Campaign, 1864 (May-August)
+
:::::150 ##$aShenandoah Valley Campaign, 1864 (May-August)
045 2#$bd186405$bd186408
+
:::::'''045''' 2#$bd186405$bd186408
 
 
150 ##$aAurignacian culture
+
:::::150 ##$aAurignacian culture
045 2#$c25000$c15000
+
:::::'''045''' 2#$c25000$c15000
Second Indicator - Undefined
+
 
Contains a blank (#).
+
:'''Second Indicator - Undefined'''
SUBFIELD CODES
+
::Contains a blank (#).
$a - Time period code
+
 
Four-character alphanumeric code derived from the "Time Period Code Table" for B.C. and C.E. time periods.
+
:'''SUBFIELD CODES'''
Each time period code associated with a heading is contained in a separate subfield $a.
+
 
Time Period Code Table
+
::'''$a - Time period code'''
B.C. (Before Common Era)
+
:::Four-character alphanumeric code derived from the "Time Period Code Table" for B.C. and C.E. time periods.
Code Time period
+
:::Each time period code associated with a heading is contained in a separate subfield $a.
a0 before 2999
+
 
b0 2999-2900
+
::'''Time Period Code Table'''
b1 2899-2800
+
 
b2 2799-2700
+
::''B.C. (Before Common Era)''
b3 2699-2600
+
 
b4 2599-2500
+
:::{|
b5 2499-2400
+
!Code
b6 2399-2300
+
!Time period
b7 2299-2200
+
|-
b8 2199-2100
+
|'''a0'''
b9 2099-2000
+
|before 2999
c0 1999-1900
+
|-
c1 1899-1800
+
|'''b0'''
c2 1799-1700
+
|2999-2900
c3 1699-1600
+
|-
c4 1599-1500
+
|'''b1'''
c5 1499-1400
+
|2899-2800
c6 1399-1300
+
|-
c7 1299-1200
+
|'''b2'''
c8 1199-1100
+
|2799-2700
c9 1099-1000
+
|-
d0 999-900
+
|'''b3'''
d1 899-800
+
|2699-2600
d2 799-700
+
|-
d3 699-600
+
|'''b4'''
d4 599-500
+
|2599-2500
d5 499-400
+
|-
d6 399-300
+
|'''b5'''
d7 299-200
+
|2499-2400
d8 199-100
+
|-
d9 99-1
+
|'''b6'''
C.E. (Common Era)
+
|2399-2300
(Add 0, 1, 2, ... 9 to each alphabetic character for the decade)
+
|-
Code Time period
+
|'''b7'''
e 1-99
+
|2299-2200
f 100-199
+
|-
g 200-299
+
|'''b8'''
h 300-399
+
|2199-2100
i 400-499
+
|-
j 500-599
+
|'''b9'''
k 600-699
+
|2099-2000
l 700-799
+
|-
m 800-899
+
|'''c0'''
n 900-999
+
|1999-1900
o 1000-1099
+
|-
p 1100-1199
+
|'''c1'''
q 1200-1299
+
|1899-1800
r 1300-1399
+
|-
s 1400-1499
+
|'''c2'''
t 1500-1599
+
|1799-1700
u 1600-1699
+
|-
v 1700-1799
+
|'''c3'''
w 1800-1899
+
|1699-1600
x 1900-1999
+
|-
y 2000-2099
+
|'''c4'''
For B.C. dates, the lowercase alphabetic character represents the millennium and the digit represents the century. If the century is not known, a hyphen (-) is used instead of a number. A single century or a period within a century is coded by repeating the appropriate two-character code to create the required four-characters.
+
|1599-1500
 +
|-
 +
|'''c5'''
 +
|1499-1400
 +
|-
 +
|'''c6'''
 +
|1399-1300
 +
|-
 +
|'''c7'''
 +
|1299-1200
 +
|-
 +
|'''c8'''
 +
|1199-1100
 +
|-
 +
|'''c9'''
 +
|1099-1000
 +
|-
 +
|'''d0'''
 +
|999-900
 +
|-
 +
|'''d1'''
 +
|899-800
 +
|-
 +
|'''d2'''
 +
|799-700
 +
|-
 +
|'''d3'''
 +
|699-600
 +
|-
 +
|'''d4'''
 +
|599-500
 +
|-
 +
|'''d5'''
 +
|499-400
 +
|-
 +
|'''d6'''
 +
|399-300
 +
|-
 +
|'''d7'''
 +
|299-200
 +
|-
 +
|'''d8'''
 +
|199-100
 +
|-
 +
|'''d9'''
 +
|99-1
 +
|}
 +
 
 +
 
 +
::''C.E. (Common Era)''
 +
::(Add 0, 1, 2, ... 9 to each alphabetic character for the decade)
 +
 
 +
:::{|
 +
!Code
 +
!Time period
 +
|-
 +
|'''e'''
 +
|1-99
 +
|-
 +
|'''f'''
 +
|100-199
 +
|-
 +
|'''g'''
 +
|200-299
 +
|-
 +
|'''h'''
 +
|300-399
 +
|-
 +
|'''i'''
 +
|400-499
 +
|-
 +
|'''j'''
 +
|500-599
 +
|-
 +
|'''k'''
 +
|600-699
 +
|-
 +
|'''l'''
 +
|700-799
 +
|-
 +
|'''m'''
 +
|800-899
 +
|-
 +
|'''n'''
 +
|900-999
 +
|-
 +
|'''o'''
 +
|1000-1099
 +
|-
 +
|'''p'''
 +
|1100-1199
 +
|-
 +
|'''q'''
 +
|1200-1299
 +
|-
 +
|'''r'''
 +
|1300-1399
 +
|-
 +
|'''s'''
 +
|1400-1499
 +
|-
 +
|'''t'''
 +
|1500-1599
 +
|-
 +
|'''u'''
 +
|1600-1699
 +
|-
 +
|'''v'''
 +
|1700-1799
 +
|-
 +
|'''w'''
 +
|1800-1899
 +
|-
 +
|'''x'''
 +
|1900-1999
 +
|-
 +
|'''y'''
 +
|2000-2099
 +
|}
 +
 
 +
 
 +
:::For '''B.C. dates''', the lowercase alphabetic character represents the millennium and the digit represents the century. If the century is not known, a hyphen (-) is used instead of a number. A single century or a period within a century is coded by repeating the appropriate two-character code to create the required four-characters.
 
 
151 #0$aRome$xHistory$yRepublic, 265-30 B.C.
+
::::151 #0$aRome$xHistory$yRepublic, 265-30 B.C.
045 ##$ad7d9
+
::::'''045''' ##$ad7d9
 
 
150 #0$aBronze age
+
::::150 #0$aBronze age
045 ##$aa-c-
+
::::'''045''' ##$aa-c-
[3000-1000 B.C.]
+
:::::''[3000-1000 B.C.]''
 
 
151 ##$aEgypt$xHistory$yEighteenth dynasty, ca. 1570-1320 B.C.
+
::::151 ##$aEgypt$xHistory$yEighteenth dynasty, ca. 1570-1320 B.C.
045 ##$ac4c6
+
::::'''045''' ##$ac4c6
For C.E. dates, the lowercase alphabetic character represents the century. A digit (0-9) is added to represent the decade. If the decade is not known, a hyphen (-) is used instead of a number. A single year or a period within a decade is coded by repeating the appropriate two-character code to create the required four characters.
+
 
 +
:::For '''C.E. dates''', the lowercase alphabetic character represents the century. A digit (0-9) is added to represent the decade. If the decade is not known, a hyphen (-) is used instead of a number. A single year or a period within a decade is coded by repeating the appropriate two-character code to create the required four characters.
 
 
151 #0$aGreat Britain$xHistory$yMedieval period, 1066-1485.
+
::::151 #0$aGreat Britain$xHistory$yMedieval period, 1066-1485.
045 ##$ao6s8
+
::::'''045''' ##$ao6s8
 
 
150 #0$aBhopal Union Carbide Plant Disaster, Bhopal, India, 1984.
+
::::150 #0$aBhopal Union Carbide Plant Disaster, Bhopal, India, 1984.
045 ##$ax8x8
+
::::'''045''' ##$ax8x8
 
 
150 #0$aCivilization, Modern$y20th century.
+
::::150 #0$aCivilization, Modern$y20th century.
045 ##$ax-x-
+
::::'''045''' ##$ax-x-
 
 
150 #0$aCatalan literature$y16th-18th centuries.
+
::::150 #0$aCatalan literature$y16th-18th centuries.
045 ##$at-v-
+
::::'''045''' ##$at-v-
 
 
151 ##$aGreece$xHistory$y146 B.C.-323 C.E.
+
::::151 ##$aGreece$xHistory$y146 B.C.-323 C.E.
045 ##$ad8h2
+
::::'''045''' ##$ad8h2
 
 
150 ##$aTwenty-first century$xForecasts.
+
::::150 ##$aTwenty-first century$xForecasts.
045 ##$ay-y-
+
::::'''045''' ##$ay-y-
$b - Formatted 9999 B.C. through C.E. time period
 
Specific time period formatted as yyyymmddhh, preceded by a code for the era (c for B.C.; d for C.E.).
 
Era and year are required components; the month, day, and hour are optional.
 
  
    era expressed as a code: c (B.C.), d (C.E.)
+
::'''$b - Formatted 9999 B.C. through C.E. time period'''
    year expressed as a four-digit number (0000 to 9999) right justified; unused positions contain zeros
+
:::Specific time period formatted as yyyymmddhh, preceded by a code for the era (c for B.C.; d for C.E.).
    month expressed as a two-digit number (01 to 12) right justified; unused positions contain zeros
 
    day expressed as a two-digit number (01 to 31) right justified; unused positions contain zeros
 
    hour expressed as a two-digit number using the 24-hour clock (00 to 23) right justified; unused positions contain zeros
 
  
First indicator position values 0-2 specify whether the time period in subfield $b is a single date, multiple dates, or a range of dates. Each 9999 B.C. through C.E. time period associated with the heading is contained in a separate subfield $b.
+
:::Era and year are required components; the month, day, and hour are optional.
 +
 
 +
:::*era expressed as a code: c (B.C.), d (C.E.)
 +
:::*year expressed as a four-digit number (0000 to 9999) right justified; unused positions contain zeros
 +
:::*month expressed as a two-digit number (01 to 12) right justified; unused positions contain zeros
 +
:::*day expressed as a two-digit number (01 to 31) right justified; unused positions contain zeros
 +
:::*hour expressed as a two-digit number using the 24-hour clock (00 to 23) right justified; unused positions contain zeros
 +
 
 +
:::First indicator position values 0-2 specify whether the time period in subfield $b is a single date, multiple dates, or a range of dates. Each 9999 B.C. through C.E. time period associated with the heading is contained in a separate subfield $b.
 
 
151 ##$aFrance$xHistory$yRevolution, 1791-1797
+
::::151 ##$aFrance$xHistory$yRevolution, 1791-1797
045 2#$bd1791$bd1797
+
::::'''045''' 2#$bd1791$bd1797
 
 
151 ##$aJapan$xHistory$yFebruary Incident, 1936 (February 26)
+
::::151 ##$aJapan$xHistory$yFebruary Incident, 1936 (February 26)
045 0#$bd19360226
+
::::'''045''' 0#$bd19360226
 
 
151 ##$aChina$xHistory$y221 B.C.-960 C.E.
+
::::151 ##$aChina$xHistory$y221 B.C.-960 C.E.
045 2#$ad7n6$bc0221$bd0960
+
::::'''045''' 2#$ad7n6$bc0221$bd0960
$c - Formatted pre-9999 B.C. time period
+
 
Formatted time period that consists of as many numeric characters as are needed to represent the number of pre-9999 years B.C.
+
::'''$c - Formatted pre-9999 B.C. time period'''
First indicator position values 0-2 specify whether the time period in subfield $c is a single date, multiple dates, or a range of dates. Each pre-9999 B.C. time period associated with the heading is contained in a separate subfield $c.
+
:::Formatted time period that consists of as many numeric characters as are needed to represent the number of pre-9999 years B.C.
 +
:::First indicator position values 0-2 specify whether the time period in subfield $c is a single date, multiple dates, or a range of dates. Each pre-9999 B.C. time period associated with the heading is contained in a separate subfield $c.
 
 
150 ##$aGeology, Stratigraphic$yMesozoic
+
::::150 ##$aGeology, Stratigraphic$yMesozoic
045 2#$c225000000$c70000000
+
::::'''045''' 2#$c225000000$c70000000
$6 - Linkage
+
 
See description of this subfield in Appendix A: Control Subfields.
+
::'''$6 - Linkage'''
$8 - Field link and sequence number
+
:::See description of this subfield in Appendix A: [http://www.loc.gov/marc/authority/ecadcntf.html Control Subfields].
See description of this subfield in Appendix A: Control Subfields.
+
 
 +
::'''$8 - Field link and sequence number'''
 +
:::See description of this subfield in Appendix A: [http://www.loc.gov/marc/authority/ecadcntf.html Control Subfields].
  
 
== INPUT CONVENTIONS ==
 
== INPUT CONVENTIONS ==
  
Punctuation - No marks of punctuation are used in field 045.
+
:'''Punctuation''' - No marks of punctuation are used in field 045.
Order of subfields - Subfield $c (Formatted pre-9999 B.C. time period) is input preceding subfield $b (Formatted 9999 B.C. through C.E. time period).
+
:'''Order of subfields''' - Subfield $c (Formatted pre-9999 B.C. time period) is input preceding subfield $b (Formatted 9999 B.C. through C.E. time period).
  
 
== CONTENT DESIGNATOR HISTORY ==
 
== CONTENT DESIGNATOR HISTORY ==
  
Indicator 1 - Type of time period in subfield $b or $c [NEW, 1979]
+
:''Indicator 1 - Type of time period in subfield $b or $c [NEW, 1979]''
  
$b - Chronological date/time [NEW, 1979]
+
:''$b - Chronological date/time [NEW, 1979]''
$c - Pre-9999 B.C. time period, formatted [NEW, 1987]
+
:''$c - Pre-9999 B.C. time period, formatted [NEW, 1987]''
Subfield $b was redefined for 9999 B.C. through C.E. time periods when subfield $c was defined for pre-9999 B.C. time periods. Prior to that time, all dates/times were contained in subfield $b.  
+
:Subfield $b was redefined for 9999 B.C. through C.E. time periods when subfield $c was defined for pre-9999 B.C. time periods. Prior to that time, all dates/times were contained in subfield $b.  
  
  
 
<p align="right">[[Kezdőlap]] - [[A MARC21 authority formátum]] - [[Authority 01X-09X]]</p>
 
<p align="right">[[Kezdőlap]] - [[A MARC21 authority formátum]] - [[Authority 01X-09X]]</p>

A lap jelenlegi, 2011. november 28., 17:32-kori változata

Kezdőlap - A MARC21 authority formátum - Authority 01X-09X


First Indicator

Type of time period in subfield $b or $c
'#' - Subfield $b or $c not present
0 - Single date/time
1 - Multiple single dates/times
2 - Range of dates/times


Second Indicator

Undefined
'#' - Undefined


Subfield Codes

$a - Time period code (R)
$b - Formatted 9999 B.C. through C.E. time period (R)
$c - Formatted pre-9999 B.C. time period (R)
$6 - Linkage (NR)
$8 - Field link and sequence number (R)

FIELD DEFINITION AND SCOPE

Time period code (subfield $a) and/or a formatted time period (subfield $b or $c) associated with a 15X heading in an established heading record or a 18X heading in a subdivision record.
Time period code in subfield $a is derived from the B.C. (Before Common Era) and/or C.E. (Common Era) lists in the Time Period Code Table provided under the description of subfield $a.

GUIDELINES FOR APPLYING CONTENT DESIGNATORS

INDICATORS
First Indicator - Type of time period in subfield $b or $c
Whether a subfield $b or $c is present in the field; and, when subfield $b or $c is present, the type of time period it contains. The values distinguish among a single date/time, multiple single dates/times, and a range of dates/times.
'#' - Subfield $b or $c not present
0 - Single date/time
Subfield $b and/or $c is present and contains a single date/time.
150 ##$aLunar petrology
045 0#$c2500000000
1 - Multiple single dates/times
Multiple $b and/or $c subfields are present, each containing a date/time. A range of dates/times is identified by value 2.
045 1#$bd1972$bd1975
[1972 and 1975]
2 - Range of dates/times
Two $b and/or $c subfields are present and together express a range of dates and/or times. Multiple single dates and/or times are identified by value 1.
150 ##$aShenandoah Valley Campaign, 1864 (May-August)
045 2#$bd186405$bd186408
150 ##$aAurignacian culture
045 2#$c25000$c15000
Second Indicator - Undefined
Contains a blank (#).
SUBFIELD CODES
$a - Time period code
Four-character alphanumeric code derived from the "Time Period Code Table" for B.C. and C.E. time periods.
Each time period code associated with a heading is contained in a separate subfield $a.
Time Period Code Table
B.C. (Before Common Era)
Code Time period
a0 before 2999
b0 2999-2900
b1 2899-2800
b2 2799-2700
b3 2699-2600
b4 2599-2500
b5 2499-2400
b6 2399-2300
b7 2299-2200
b8 2199-2100
b9 2099-2000
c0 1999-1900
c1 1899-1800
c2 1799-1700
c3 1699-1600
c4 1599-1500
c5 1499-1400
c6 1399-1300
c7 1299-1200
c8 1199-1100
c9 1099-1000
d0 999-900
d1 899-800
d2 799-700
d3 699-600
d4 599-500
d5 499-400
d6 399-300
d7 299-200
d8 199-100
d9 99-1


C.E. (Common Era)
(Add 0, 1, 2, ... 9 to each alphabetic character for the decade)
Code Time period
e 1-99
f 100-199
g 200-299
h 300-399
i 400-499
j 500-599
k 600-699
l 700-799
m 800-899
n 900-999
o 1000-1099
p 1100-1199
q 1200-1299
r 1300-1399
s 1400-1499
t 1500-1599
u 1600-1699
v 1700-1799
w 1800-1899
x 1900-1999
y 2000-2099


For B.C. dates, the lowercase alphabetic character represents the millennium and the digit represents the century. If the century is not known, a hyphen (-) is used instead of a number. A single century or a period within a century is coded by repeating the appropriate two-character code to create the required four-characters.
151 #0$aRome$xHistory$yRepublic, 265-30 B.C.
045 ##$ad7d9
150 #0$aBronze age
045 ##$aa-c-
[3000-1000 B.C.]
151 ##$aEgypt$xHistory$yEighteenth dynasty, ca. 1570-1320 B.C.
045 ##$ac4c6
For C.E. dates, the lowercase alphabetic character represents the century. A digit (0-9) is added to represent the decade. If the decade is not known, a hyphen (-) is used instead of a number. A single year or a period within a decade is coded by repeating the appropriate two-character code to create the required four characters.
151 #0$aGreat Britain$xHistory$yMedieval period, 1066-1485.
045 ##$ao6s8
150 #0$aBhopal Union Carbide Plant Disaster, Bhopal, India, 1984.
045 ##$ax8x8
150 #0$aCivilization, Modern$y20th century.
045 ##$ax-x-
150 #0$aCatalan literature$y16th-18th centuries.
045 ##$at-v-
151 ##$aGreece$xHistory$y146 B.C.-323 C.E.
045 ##$ad8h2
150 ##$aTwenty-first century$xForecasts.
045 ##$ay-y-
$b - Formatted 9999 B.C. through C.E. time period
Specific time period formatted as yyyymmddhh, preceded by a code for the era (c for B.C.; d for C.E.).
Era and year are required components; the month, day, and hour are optional.
  • era expressed as a code: c (B.C.), d (C.E.)
  • year expressed as a four-digit number (0000 to 9999) right justified; unused positions contain zeros
  • month expressed as a two-digit number (01 to 12) right justified; unused positions contain zeros
  • day expressed as a two-digit number (01 to 31) right justified; unused positions contain zeros
  • hour expressed as a two-digit number using the 24-hour clock (00 to 23) right justified; unused positions contain zeros
First indicator position values 0-2 specify whether the time period in subfield $b is a single date, multiple dates, or a range of dates. Each 9999 B.C. through C.E. time period associated with the heading is contained in a separate subfield $b.
151 ##$aFrance$xHistory$yRevolution, 1791-1797
045 2#$bd1791$bd1797
151 ##$aJapan$xHistory$yFebruary Incident, 1936 (February 26)
045 0#$bd19360226
151 ##$aChina$xHistory$y221 B.C.-960 C.E.
045 2#$ad7n6$bc0221$bd0960
$c - Formatted pre-9999 B.C. time period
Formatted time period that consists of as many numeric characters as are needed to represent the number of pre-9999 years B.C.
First indicator position values 0-2 specify whether the time period in subfield $c is a single date, multiple dates, or a range of dates. Each pre-9999 B.C. time period associated with the heading is contained in a separate subfield $c.
150 ##$aGeology, Stratigraphic$yMesozoic
045 2#$c225000000$c70000000
$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.

INPUT CONVENTIONS

Punctuation - No marks of punctuation are used in field 045.
Order of subfields - Subfield $c (Formatted pre-9999 B.C. time period) is input preceding subfield $b (Formatted 9999 B.C. through C.E. time period).

CONTENT DESIGNATOR HISTORY

Indicator 1 - Type of time period in subfield $b or $c [NEW, 1979]
$b - Chronological date/time [NEW, 1979]
$c - Pre-9999 B.C. time period, formatted [NEW, 1987]
Subfield $b was redefined for 9999 B.C. through C.E. time periods when subfield $c was defined for pre-9999 B.C. time periods. Prior to that time, all dates/times were contained in subfield $b.


Kezdőlap - A MARC21 authority formátum - Authority 01X-09X