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MARC Tag Talk with Cassidy Cataloguing - 100 Field

The 100 Main Entry Personal Name

What is it?

The 100 field is reserved for the Personal Name of the main contributor of the title. The term "Main Entry" harkens back to the days of traditional card catalogs where multiple cards were created to reference back and forth. The 'Main Entry' catalog card would contain the most comprehensive information about the title.

When the main contributor of a title is a group or corporation, another 1xx is used and when multiple authors are involved they are placed after the main author in the 7xx but we are just chatting about the 100 Main Entry Personal Name today.

Where do I find it?

The 100 Main Entry Personal Name is not repeatable. When adding a 100 field in a record, use the first author name from the title page of the resource. If there are multiple authors, the names after the first name are to be included in a 700 tag.

The 100 field may include one or many subfields.

The examples below will include the $e since we catalog using RDA guidelines, but your library may not use them.

Utilize the Library of Congress Authorities to find the authorized version of an author's name. Each version of their site has its pros and cons.

Authorities will be a later chat in more detail, but another source for Authorities can be found at the Virtual International Authority File.

Indicators for this field are as follows:

First Indicator

0 - Forename - this is reserved for main contributors who are known by their forename

100 0_ Madonna,$d1958-$eauthor.

100 0_ Aristotle,$eauthor.

1 - Surname - this is reserved for main contributors known by a full first and last name (and sometimes many other attributes!)

100 1_ Henkow, Oskar,$eauthor.

100 1_ Dixon, Owen,$cSir,$d1886-1972,$eauthor.

3 - Family Name - this is reserved for contributors as members of a family. In our line of cataloging we don't come across this very often, but a genealogy library may utilize this more often (although a family name contributor would likely be found in the 700s). It is a valid field, however!

100 3_ Barner family.

100 3_ Latta family.

Second Indicator

Second indicator is always undefined (blank).

Subfield options - Following are the more common subfields used in the 100 field. There are others that are valid, but not likely to be found in the 100.

$a - the $a is mandatory in a 100. This non-repeatable field is for the Personal Name. The $a can include a middle name or initial, it depends on the authorized version.

100 1_ $aHenkow, Oskar,$eauthor.

100 1_ $aLock, Jennifer Ann,$eauthor.

100 1_ $aThomas, Adrian L. R.,$eauthor.

$b - Numeration (Not repeatable in this field)

This subfield is for Roman numerals when used alone or in conjunction with a forename. A regular person who is a second or fourth in their family (II or IV) would include their numeration in a $c.

100 0_ $aJohn Paul$bII,$cPope,$d1920-$eauthor.

100 0_ $aJames$bII,$cKing of England,$d1633-1701,$eauthor.

$c - Titles or Words Associated with a Name (Repeatable subfield)

This subfield is for additional information associated with a Personal Name such as a title. When a name is somewhat popular, the $c can add a job title or field in order to differentiate.

100 1_ $aJones, Katie$c(Analyst in housing policy),$eauthor.

100 1_ $aCox, Daniel$c(Religion and public life researcher),$eauthor.

100 1_ $aGould, William B.,$cIV,$eauthor.

$d - Date Associated with a Name (Not Repeatable in this field)

If only a birth year is known or the author is still living, see example 1.

If only a death year is known, see example 2.

If both, see example 3.

If a date is 'approximately' a date or documented as multiple dates, see example 4.

If a date is between a few years, see example 4 and 5.

If a date is approximate, see example 6.

1. 100 1_ $aHawkes, Charles Pascoe,$d1877-$eauthor.

2. 100 1_ $aAnderson, Andrew J.,$d-1927,$eauthor.

3. 100 1_ $aField, David Dudley,$d1805-1894,$eauthor.

4. 100 1_ $aThomas,$cà Becket, Saint,$d1118?-1170,$eauthor.

5. 100 1_ $aHawārī, ʻAbd al-Salām ibn Muḥammad,$d1842 or 1843-1910 or 1911,$eauthor.

6. 100 1_ $aKey, Adriaen Thomasz,$dapproximately 1545-approximately 1589,$eauthor.

$e - Relator Term (Repeatable subfield if the person held more than one role such as the author and editor)

This term identifies the role of this person on the work. These terms are preceded by a comma unless the previous subfield ends in a dash (as example 1 below)

Library of Congress List of Relators

100 1_ $aRoth, Daniel,$d1942-$einterviewee.

100 1_ $aMastriano, Douglas V.,$eproject director.

100 1_ $aBrauer, David A.,$eauthor,$eeditor.

$q - Fuller Form of Name (Not Repeatable in this field)

If an author is colloquially known by an initial or shortened version of their name, sometimes a $q is added to include the fuller name. These fuller names are entered in parentheses with no preceding punctuation (no comma).

100 1_ $aPérez González, A. Beatriz$q(Ana Beatriz),$d1963-$eauthor.

100 1_ $aTolkien, J. R. R.$q(John Ronald Reuel),$d1892-1973,$eauthor.

100 1_ $aSalinger, J. D.$q(Jerome David),$d1919-2010,$eauthor.

Additional Fields

If a piece has multiple authors or editors the main author will go in the 100 field and additional authors or contributors will go in a 700 Added-Entry Personal Name field.

Ask us anything and we will be happy to have one of our seasoned professionals answer to the best of our ability.

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