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Reframing Description
A Practical Introduction to Linked Data and 
the Bibliographic Universe
Brinna Michael, Emory University

ABSTR AC T Linked data has been on the tongues and minds of 
librarians for years, but the concept still manages to remain some-
what mysterious and unreachable to the broader technical services 
community. Recognizing the broad divide between the complex 
conceptual debates and the reality of practical application, this 
session seeks to bridge this gap. In providing an entry-level intro-
duction to the practice of using linked data to represent biblio-
graphic descriptions, this session also seeks to spark interest in 
further participation in the wider linked data movement.

Linked data as the practice of encoding information so that it can 
be contextually connected to other information by defining rela-
tionships in a way that is machine readable/actionable. By defining 
and identifying data in this way, it is possible for machines to begin 
processing that information in a way that mimics the manner in 
which human brains draw connections between concepts. But why 
is this important? Traditional methods of encoding and recording 
bibliographic data store concepts as strings and do not provide a 
means for the machine to independently extract meaning from those 
strings. As illustrated in figure 1, the human brain can see a set of 
four completely different strings and 1) recognize that they are all 
actually representing the same idea, and 2) recall other concepts 
related to the strings. Given that same list, a machine algorithm will 
only recognize the strings as completely separate entities unless it is 
provided with an encoding framework that defines them otherwise.

It is this divide between human cognitive and machine data 
processing that linked data practices strive to bridge. From the 
beginning, this goal has been intrinsically tied to the concept of the 
Semantic Web, defined by Oxford English Dictionary (3rd ed. 2014) 
as “a proposed development of the World Wide Web in which data 
in web pages is structured and tagged in such a way that it can be 
read directly by computers . . .” However, Tim Berners-Lee and his 



Listen and Learn Sessions  235

colleagues (2001) took this a step further, presenting the Semantic 
Web as “an extension of the current web in which information is 
given well-defined meaning, better enabling computers and people 
to work in cooperation.” 

If the Semantic Web is the end goal, linked data practices are 
the means to attain it. In his work to realize a functional Semantic 
Web, Berners-Lee (2009) defined the following core requirements 
for linked data:

1) Use URIs as names for things.
2) Use HTTP URIs so that people can look up those names.
3) When someone looks up a URI, provide useful information, 

using the standards (RDF, SPARQL, etc.).
4) Include links to other URIs so that they can discover more 

things.

The first requirement, to use URIs (Universal Resource Identifiers) as 
names for “things,” including concepts, ideas, people, places, objects, 
and more, is the core of functional linked data. URIs can be any string 
of characters and/or numbers, but the most important aspect is 
that the URI must be unique to the thing it is naming. Requirement 
two further specifies that URIs should be HTTP compliant, making 
them searchable on the internet. This compliance lays the ground-
work for linking these URIs in a way that is machine-actionable. 
The third and fourth requirements give linked data its purpose and 
function. Simply assigning URIs to things is important but, without 
additional context, they lose functionality. To make that contextu-
alization usable by machines, and further the goal of improving 
human/machine cooperation, using encoding standards like RDF 
or SPARQL is critical. Finally, connections and links must be made 
between URIs to build a system of pathways for machines to follow 
to better facilitate discovery. Without creating these initial links 

FIGURE 1: Comparison of human cognitive and machine data processing of strings.



236  AT L A 2020 PROCEEDINGS

and thereby defining these relationships, the data remains static 
and unusable.

LINKED DATA AS STRUCTURE

As previously mentioned, traditional methods of encoding biblio-
graphic data have taught us to think of that data in terms of records—
flat, isolated, and often strictly string-based. Each record is separate 
from each other and does not offer a machine-readable connection to 
other records. Linked data, however, operates as a network structure 
that is, by nature, dynamic and interconnected, utilizing the machine 
actionability of HTTP-compliant URIs. A network structure allows 
for easier use and reuse of data in reference to each other.

To illustrate this, consider the following scenario: below are two 
partial MARC records for books that share a specific set of character-
istics, including subjects, content type, mediation type, and carrier 
type.

Table 1: Comparison of Related MARC Records
BOOK 1 BOOK 2

FIELD CONTENT FIELD CONTENT

100 $a Tolkien, J. R. R. $q 
(John Ronald Reuel), 
$d 1892-1973.

100 Wood, Ralph C.

245 $a The lord of the 
rings / $c J.R.R. 
Tolkien.

245 $a The gospel 
according to Tolkien 
: $b visions of the 
Kingdom in Middle-
earth / $c Ralph C. 
Wood.

250 $a Seven volume 
edition; Millennium 
edition.

264 $a London : $b 
HarperCollins, $c 
1999.

264 $a Louisville, Ky. : $b 
Westminster John 
Knox PRess, $c [2003].

264 $c ©1966 264 $c ©2003

336 $a text $b txt $2 
rdacontent

336 $a text $b txt $2 
rdacontent



Listen and Learn Sessions  237

Table 1: Comparison of Related MARC Records
BOOK 1 BOOK 2

FIELD CONTENT FIELD CONTENT

337 $a unmediated $b n 
$2 rdamedia

337 $a unmediated $b n 
$2 rdamedia

338 $a volume $b nc $2 
rdacarrier

338 $a volume $b nc $2 
rdacarrier

600 $a Baggins, Frodo $v 
Fiction.

600 $a Tolkien, J. R. R. 
$q(John Ronald 
Reuel), $d1892-1973. 
$t Lord of the rings.

600 $a Tolkien, J. R. R. $q 
(John Ronald Reuel), 
$d 1892-1973 $x 
Religion.

650 $a Middle Earth 
(Imaginary place) $v 
Fiction.

650 $a Christianity and 
literature $z England 
$x History $y 20th 
century.

650 $a Fantasy fiction, 
English $x History 
and criticism.

650 $a Christian ethics in 
literature.

650 $a Middle Earth 
(Imaginary place).

As MARC records, these similarities can only be connected by use 
of string-matching methods, which rely on flawless data entry to 
create consistent matches. Such a need is partially responsible for the 
robust and strict formatting and data entry requirements set forth 
by the MARC standard and RDA (Resource Description and Access). 

The first step towards reframing these two records as a network 
of interconnected data points is to identify the common concepts 
between the two. In table 2, we can see the concept or value and 
its relationship to the book it is describing. Note that in the case of 

“Tolkien, J. R. R. (John Ronald Reuel), 1892-1973,” the relationships 
between the name and the books it is describing are different, yet it 
still constitutes a point of connection between the two books.



238  AT L A 2020 PROCEEDINGS

Table 2: String and URI descriptive values in relation to two 
books

STRING VALUE URI BOOK 1 
Relationship

BOOK 2 
Relationship

Tolkien, J. R. R. 
(John Ronald 
Reuel), 1892-1973

http://id.loc.gov/
authorities/
names/n79005673

author subject

text http://id.loc.gov/
vocabulary/
contentTypes/txt

content content

unmediated http://id.loc.gov/
vocabulary/
mediaTypes/n

mediation mediation

volume http://id.loc.gov/
vocabulary/
carriers/nc 

carrier carrier

Middle Earth 
(Imaginary place)

http://id.loc.gov/
authorities/
subjects/
sh85085022

subject subject

With these values identified, the next step is to locate or create a 
unique URI to represent the concept. In the case of this example, each 
of these values has already emerged from existing controlled vocab-
ularies—courtesy of the Library of Congress (LC)—which have been 
fully converted to linked data in an effort to expand linked data prac-
tices within the wider cultural heritage community. In the URI 
column of table 2, you can see the URIs that represent each of the 
chosen values.

FIGURE 1: Network of shared relationships between two books and five descriptive 
values. School textbook, textbook icon by Boca Tutor, found at www.iconfinder.com/
icons/1741323/school_textbook_textbook_icon, used under a CC BY-SA 3.0 license.

http://id.loc.gov/authorities/names/n79005673
http://id.loc.gov/authorities/names/n79005673
http://id.loc.gov/authorities/names/n79005673
http://id.loc.gov/vocabulary/contentTypes/txt
http://id.loc.gov/vocabulary/contentTypes/txt
http://id.loc.gov/vocabulary/contentTypes/txt
http://id.loc.gov/vocabulary/mediaTypes/n
http://id.loc.gov/vocabulary/mediaTypes/n
http://id.loc.gov/vocabulary/mediaTypes/n
http://id.loc.gov/vocabulary/carriers/nc 
http://id.loc.gov/vocabulary/carriers/nc 
http://id.loc.gov/vocabulary/carriers/nc 
http://id.loc.gov/authorities/subjects/sh85085022
http://id.loc.gov/authorities/subjects/sh85085022
http://id.loc.gov/authorities/subjects/sh85085022
http://id.loc.gov/authorities/subjects/sh85085022
http://www.iconfinder.com/icons/1741323/school_textbook_textbook_icon
http://www.iconfinder.com/icons/1741323/school_textbook_textbook_icon


Listen and Learn Sessions  239

The next step is to create links between the two books being 
described by defining their relationships to the URIs that represent 
the identified descriptive values. Figure 1 provides a visual represen-
tation of the network structure of these relationships. In the diagram, 
the book icons represent the core URIs that would represent the 
physical books being described. The labeled arrows denote URIs for 
the predefined relationships as described in common schemas such 
as Dublin Core or Schema.org. Finally, the central column lists the 
URIs for the previously identified descriptive values.

These structures, known as triples, are the foundation of linked 
data, and can be expanded almost indefinitely through the use of 
URIs. For example, figure 1 represents a fragment of the wider 
network to which these two metadata sets belong. If we expand our 
view of the network describing these two books (figure 2), we see 
additional descriptive URIs that are not shared with one another but 
may link each book to even more resources. Each of these relation-
ships could start its own networked pathway of connections to a 
wide web of other ideas and resources. However, those relationships 
must first be defined and the links created, so that a machine can be 
guided through the logical thought process that human brains follow 
naturally.

LINKED DATA AS CONTENT

Having laid out the way in which structuring the relationships 
between data creates a wider network, it is important to consider 
how the actual content of the data works to further the goal of 
human/machine cooperability. Using one of the descriptive values 

FIGURE 2: Extended network of relationships between two books and descriptive 
values. School textbook, textbook icon by Boca Tutor, found at www.iconfinder.com/
icons/1741323/school_textbook_textbook_icon, used under a CC BY-SA 3.0 license.

http://www.iconfinder.com/icons/1741323/school_textbook_textbook_icon
http://www.iconfinder.com/icons/1741323/school_textbook_textbook_icon


240  AT L A 2020 PROCEEDINGS

from before, it is important to remember that, in assigning names, 
strings, or URIs to things in the real world, a placeholder is being 
created for that thing in the digital environment. 

For example, J. R. R. Tolkien was a real person who lived, worked, 
and wrote. He, as a specific and unique person, is represented by LC 
with the string “Tolkien, J. R. R. (John Ronald Reuel), 1892-1973” and 
the URI, http://id.loc.gov/authorities/names/n79005673. But how are 
these two connected? The string is human readable, yet a machine 
cannot parse that it is made up of a surname, initials, a first and 
middle names, and his dates of birth and death. On the other hand, 
the URI is machine readable and actionable, yet there is no way 
a human would know it was a place holder for J. R. R. Tolkien if 
presented only with the URI.

This is where the contextualization of data, those third and fourth 
core requirements laid out by Berners-Lee, becomes important. 
Table 3 presents an excerpt from the RDF (Resource Description 
Framework) document underlying the human display version of the 
entry for Tolkien in the LC’s linked data service:

Table 3: RDF serialization of LC term “Tolkien, J. R. R. ( John Ron-
ald Reuel), 1892-1973

SCRIPTA

1 <rdf:RDF xmlns:skos=“http://www.w3.org/2004/02/skos/
core#”

2 xmlns:rdf=“http://www.w3.org/1999/02/22-rdf-syntax-ns#”

3 xmlns:rdfs=“http://www.w3.org/1999/02/22-rdf-schema#”

4 xmlns:cs=“http://purl.org/vocab/changeset/schema#”

5 xmlns:skosxl=“http://www.w3.org/2008/05/skos-xl#”>

6    <rdf:Description   rdf:about=“http://id.loc.gov/authorities/
names/n79005673”>

7         <rdf:type   rdf:resource=“http://www.w3.org/2004/02/
skos/core#Concept”/>

8         <skos:prefLabel>Tolkien, J. R. R. (John Ronald Reuel), 
1892-1973</skos:prefLabel>

9 ...

a Taken from the “SKOS – RDF/XML” format available for 
download at id.loc.gov/authorities/names/n79005673.

http://id.loc.gov/authorities/names/n79005673
http://www.w3.org/2004/02/skos/core#
http://www.w3.org/2004/02/skos/core#
http://www.w3.org/1999/02/22-rdf-syntax-ns#
http://www.w3.org/1999/02/22-rdf-schema#
http://purl.org/vocab/changeset/schema#
http://www.w3.org/2008/05/skos-xl#
http://id.loc.gov/authorities/names/n79005673
http://id.loc.gov/authorities/names/n79005673
http://www.w3.org/2004/02/skos/core#Concept
http://www.w3.org/2004/02/skos/core#Concept
http://id.loc.gov/authorities/names/n79005673


Listen and Learn Sessions  241

Lines 1–5 consist of the declaration of the encoding schemes which 
give definition to the relationships being drawn—in this case, 
RDF, RDFS (RDF Schema), SKOS (Simple Knowledge Organization 
System), SKOS-XL (an extension of SKOS), and Changeset. Declar-
ing namespaces in this way defines a short prefix to represent the 
base URI for the identified schema throughout the remainder of the 
document. Line 6 declares what concept will be described by the 
document, in this case the URI http://id.loc.gov/authorities/names/
n79005673. Finally, in line 8, the “skos:prefLabel,” a human-readable 
label, is assigned to the URI as “Tolkien, J. R. R. (John Ronald Reuel), 
1892-1973.” These three aspects work together to embody a human 
and machine cooperative representation of Tolkien in a digital envi-
ronment, which can be seen when following the active URI link.

LINKED DATA AND BIBLIOGRAPHIC DESCRIPTION

Although linked data may seem far away as a daily practice, there 
are already aspects of that practice ingrained into common catalog-
ing and descriptive metadata procedures. Use of controlled vocabu-
laries has been common and required for decades in most standard 
descriptive best practices. In fact, it would only take a small leap from 
using the string values found in controlled vocabularies to using 
URIs from those same vocabularies to begin satisfying Berners-Lee’s 
first core requirement. A large number of vocabularies encoded 
as linked data already exist, including the majority of LC’s vocab-
ularies, the Getty vocabularies (Art and Architecture Thesaurus, 
Union List of Artist Names, etc.), FAST (Faceted Application of Subject 
Terminology), VIAF (Virtual Internet Authority File), and many more 
domain-specific vocabularies. In recent years, catalogers also began 
experimentally use $0 and $u in MARC records to integrate action-
able URIs into records, beginning the process of shifting descriptive 
norms away from simply providing the string placeholder to provid-
ing both a string and URI. Finally, the very practice of copy cataloging 
reflects aspects of linked data practice, namely the improvement of 
efficiency in descriptive practices as well as the reduction of unnec-
essary duplication of work and data.

With this in mind, what changes might we expect to see as the 
world of bibliographic description shifts further towards a linked 
data baseline? We can certainly expect changes within cataloging 
software, including back-end integration with controlled vocabu-

http://id.loc.gov/authorities/names/n79005673
http://id.loc.gov/authorities/names/n79005673


242  AT L A 2020 PROCEEDINGS

laries encoded as linked data, potentially in the form of dropdowns 
or search suggestion features in the cataloging interface. Coopera-
tive cataloging platforms, like OCLC Connexion, may look slightly 
different, perhaps with an interface that more closely resembles a 
webform, rather than the familiar MARC record input screen. Along-
side the changes to cataloging interfaces, discovery layers may begin 
to include more options for customization to enable users to custom-
ize their search experience in ways that were previously impossible, 
including improved search filters and, potentially, the ability to select 
the desired display language. Additionally, with bibliographic data 
encoded as linked data, bibliographic information will be able to 
be exposed via discovery layers to large search engine algorithms, 
making our holdings more openly accessible to potential users on a 
broad scale. Finally, changes to our conceptual cataloging and meta-
data frameworks have already been seen and will continue to be 
seen, including changes from a strictly FRBR (Functional Require-
ments for Bibliographic Description)-based RDA to an IFLA-LRM 
(Library Reference Model)-based RDA. Alongside these changes, 
there will be an increased need to work towards assigning URIs to 
some of the more complex conceptual aspects of bibliographic enti-
ties, like Work and Instance.

Such changes require a wide variety of technical services roles to 
support them. Software developers and programmers will be called 
on to develop this new front- and back-end software to support cata-
loging and discovery. As that software is developed, systems manag-
ers and systems librarians will need to keep pace with maintaining 
and supporting the functionality of these systems. Catalogers and 
metadata librarians will have to adapt to new input mechanisms 
and accept a level of disruption in their workflows and consistency, 
which accompanies the shifting of technologies and conceptual 
models. Luckily, many technical services individuals have experi-
enced shifts from one ILS (Integrated Library System) to another—
an experience which is likely to feel quite similar to a transition into 
a linked data system. Most importantly, it is important to recognize 
that such a transition is an extended process, requiring interdepart-
mental cooperation and a willingness to contribute and step outside 
our comfort zones.



Listen and Learn Sessions  243

CONCLUSION

We can already see aspects of a linked-data, bibliographic future 
coming to life. ExLibris has begun experimenting with automati-
cally generating BIBFRAME (Bibliographic Framework) records from 
existing MARC records in the Alma system (ExLibris, “BIBFRAME”). 
These generated records include a number of automatically encoded 
URIs for descriptive metadata, including the resource language, 
content type, and mediation, which are drawn from LC’s linked data 
service. Even some validated headings, such as names and subjects, 
have URIs pulled from VIAF and the LC Subject Headings and Name 
Authority Files.

On the search and discovery front, linked data will connect librar-
ies with a wider audience through major search engines. For exam-
ple, when searching for a book on Google, a helpful sidebar is 
included on every results page. All the information contained in that 
sidebar is enabled through some form of linked data, drawing on 
sources such as Wikipedia, Google Books, Goodreads, and more. 
Recently, a search for Lord of the Rings showed a new section in this 
sidebar entitled, “Borrow.” Under this section, information on e-book 
holdings from local libraries was displayed with a link to the library’s 
catalog record.

FIGURE 3: Extended network of relationships between two books and descriptive 
values.



244  AT L A 2020 PROCEEDINGS

For now, it seems that third-party providers, such as Hoopla and 
Overdrive, are responsible for enabling this exposure of biblio-
graphic and holdings description to search engines. Nevertheless, it 
shows a very real opportunity for connecting with users who may 
not be comfortable searching a library catalog.

While a fully linked-data bibliographic world is still years away, 
the process of shifting away from the static, records-based processes 
that have been the staple of descriptive procedures for decades has 
already begun in full force. In practice, the creation of linked-data 
networks and the use of linked-data behaviors are not so far from 
what has been the current norms, but we must be willing to embrace 
these changes fully as we move forward.

WORKS CITED

Berners-Lee, Tim. “Linked Data.” Updated June 18, 2009. www.
w3.org/DesignIssues/LinkedData.html.

Berners-Lee, Tim, James Hendler, and Ora Lassila. 2001. “The 
Semantic Web: A New Form of Web Content That Is Meaning-
ful to Computers Will Unleash a Revolution of New Possibilities.” 
Scientific American, May.

ExLibris. n.d. “BIBFRAME.” ExLibris Developer Network. Accessed 
June 30, 2020. developers.exlibrisgroup.com/alma/integrations/
linked_data/bibframe. 

Library of Congress. n.d. “Tolkien, J. R. R. (John Ronald Reuel), 1892-
1973.” Updated August 9, 2019. id.loc.gov/authorities/names/
n79005673.

http://www.w3.org/DesignIssues/LinkedData.html
http://www.w3.org/DesignIssues/LinkedData.html
http://developers.exlibrisgroup.com/alma/integrations/linked_data/bibframe
http://developers.exlibrisgroup.com/alma/integrations/linked_data/bibframe
http://id.loc.gov/authorities/names/n79005673
http://id.loc.gov/authorities/names/n79005673

