A practical case study of how to create Linked Open Data for 1.300 Dutch underground newspapers from World War 2 using Wikipedia, DBpedia and an old paper book. Lecture given by Olaf Janssen - Wikimedia & Open Data coordinator for the National Library of the Netherlands (KB) - for students of the master's course "Digital Access to Cultural Heritage" at Leiden University on 3-3-2016

1. LOD case study: WW2 underground
newspapers on Wikipedia
Digital Access to Cultural Heritage, Leiden University, 3-3-2016
Olaf Janssen (Koninklijke Bibliotheek)
olaf.janssen@kb.nl - @ookgezellig

2. What I hope you’ll learn today
1. How to give a new life to an old paper book
2. How to get 1.300 newspapers from WW2 on Wikipedia
While doing 1 and 2:
3. The advantages of linked open data
(= downsides of unconnected data sources)
Olaf Janssen
Wikipedia &
Open data coordinator
National library of the
Netherlands

3. http://www.4en5meiamsterdam.nl/attachment/47454

4. During WW2
± 1.300 Dutch underground
newspaper titles have been
issued in NL
In every shape & form…
http://www.4en5meiamsterdam.nl/attachment/47454

5. http://resolver.kb.nl/resolve?urn=ddd:010436323 http://resolver.kb.nl/resolve?urn=ddd:010442948
http://resolver.kb.nl/resolve?urn=ddd:010447825 http://resolver.kb.nl/resolve?urn=ddd:010450508
From well-known
big titles
(o.a. Parool, Vrij Nederland, Trouw, de Waarheid)

6. To very small, home-made, pamphlet-like
issues

7. After the war many titles have
been (physically) preserved at the NIOD …
The national Institute for War, Holocaust and
Genocide Studies in Amsterdam
By Romaine - Own work, CC0, https://commons.wikimedia.org/w/index.php?curid=37072767

8. https://commons.wikimedia.org/wiki/File:Verzetskrant_in_archiefdozen_bij_het_NIOD.jpg – CC-BY-SA - OlafJanssen

9. By Romaine - Own work, CC0,
https://commons.wikimedia.org/w/index.php?curid=37072734

10. These 1.300 newspapers have been
described in the KB-catalogue…
Bibliographic
metadata
Like this one, De Geus onder studenten

11. PPN
= unique ID of this title
in KB-catalogue
http://opc4.kb.nl/DB=1/PPN?PPN=107123223

12. These newspapers were digitised page by page…
resulting in …

13. ... full texts in Delpher
http://resolver.kb.nl/resolve?urn=ddd:010424553:mpeg21:p001
• Scans
• Full-text OCR

14. Again, De Geus onder studenten

15. http://www.delpher.nl/nl/kranten/results?coll=d
ddtitel&cql[]=ppn+any+(107123223)
PPN
= unique ID of this title in Delpher
(same at for KB-catalogue)
Again, De Geus onder studenten

16. On Delpher you can read and (word)search
this title...

17. Say I want to know more about this newspaper
• What sort/style of underground paper was De Geus?
• What is the history of this newspaper?
• Who were working on it?
• Where was this newpaper printed?
• How was De Geus distributed and financed?
• Were there any relations with other illegal newspapers or resistance
groups?
• Etc…
Under “Details” perhaps?

18. OK ok, some metadata…
.. but I want to know móóór….

19. Maybe in the
catalogue record??

21. Problem with Delpher
(and KB-catalogue)
Véry little contextual information
about the newspaper(title)s
https://thejungleisneutral.files.wordpress.com/2013/11/lost.jpg

22. Question:
Where would most people start searching contextual
information about De Geus onder studenten?
Probably Wikipedia! (via Google)

23. http://nl.wikipedia.org/wiki/De_Geus_onder_studenten_(verzetsblad)
Question:
Where would most people start searching contextual
information about De Geus onder studenten?
Probably Wikipedia! (via Google)

24. https://www.youtube.com/watch?v=VREJV--VHSw

25. Report on interest in WW2 among Dutch population
http://www.oorlogsbronnen.nl/gebruikersonderzoek2015, May 2015

26. Many of us use the internet to search for
information [..]. We often mention Wikipedia…

27. Everything is of course on Wikipedia. Just type in a
name and you can read entire essays... (man 70s)

28. Over half of us think that Wikipedia and Google
contribute to our knowledge and understanding of
history
When we have to find information about WW2 outside
the class setting, we fully concentrate on digital
resources like Google and Wikipedia. (school kids)

29. http://www.delpher.nl/nl/kranten/results?coll=dddtitel&cql[]=ppn+any+(107123223)
http://nl.wikipedia.org/wiki/De_Geus_onder_studenten_(verzetsblad)
is given in
Context about
De Geus onder studenten

30. But now…
We have another
problem…

31. https://nl.wikipedia.org/wiki/Categorie:Illegale_pers_in_de_Tweede_Wereldoorlog
… De Geus on Wikipedia is an exception
1. Very few underground newspapers
have their own WP articles
2. The overview of these newspapers
on WP is far from complete

32. Good news!
http://www.archives.gov/research/military/ww2/photos/images/ww2-194.jpg
There is a 1-fix solution to
this contextual problem!

33. De Ondergrondse Pers 1940-1945
By Lydia E. Winkel & H. de Vries
1989, ISBN 9021837463
Veen Uitgevers
This book
(“De Winkel”) contains
contextual articles
about
(nearly) all ± 1.300
illegal WW2
newspapers

34. “De Winkel” – nr. 199
De Ondergrondse Pers 1940-1945 ,
Lydia E. Winkel, H. de Vries , 1989,
ISBN 9021837463,
Veen Uitgevers

35. Every article has a
unique ID
(“Winkel-ID”)

36. Every article has metadata
• Title, subtitle, motto
• Place of publication
• Period of publication
• Publication frequency (daily, weekly, one-off, irregular)
• Multiplication (stenciled, printed, typed, handwritten)
• Contents (news, opinions, poems, illustrations, humor)
• Number of prints (min – max)

37. Relation 1/3
Newspaper  Placename
 semantics, linked data

38. Relation 1/3
Newspaper  Placename
 semantics, linked data

39. Contextual
information
 Nice material
for a
Wikipedia article

40. Very often persons related to this
newspaper are mentioned

41. Relation 2/3
Newspaper  Persons
 semantics, linked data

42. Many articles also contain
references to other newspapers
• 106 = Cereales Vadeness (students resistance, newspaper Wageningen)
• 360 = Leidsche Brief (students resistance newspaper, Leiden)
• 748 = Sol Justitiae (students resistance newspaper, Utrecht)

43. Relation 3/3
Newspaper  Other newspapers
 semantics, linked data

44. http://https://knowledgeutopia.files.wordpress.com/2014/01/hollandhouselibraryblitz1940.j
pg
Too bad it’s a paper book
 hard to find, multiply, distribute and build upon

45. We need it digital!!
http://https://knowledgeutopia.files.wordpress.com/2014/01/hollandhouselibraryblitz1940.j
pg

46. We need it digital!!
1. Clear copyright with copyright holder (NIOD)
 Open CC-BY-SA license
2. Scan & OCR
3. Convert into PDF
4. Put online: NIOD site & Wikimedia Commons

47. De Winkel as PDF on NIOD website (CC-BY-SA)
http://www.niod.nl/nl/de-ondergrondse-pers-1940-1945

48. De Winkel as PDF on Wikimedia Commons
https://commons.wikimedia.org/wiki/File:PDF_of_De_Ondergrondse_Pers_1940-1945_-_derde_druk_-_1989.pdf

49. De Winkel as PDF on NIOD website (CC-BY-SA)
http://www.niod.nl/nl/de-ondergrondse-pers-1940-1945
Saved us €13.330!
http://www.brill.com/dutch-underground-press-1940-1945

50. Wikipedia article about De Winkel
http://nl.wikipedia.org/wiki/De_ondergrondse_pers_1940-1945

51. Wikipedia article about the author
http://nl.wikipedia.org/wiki/Lydia_Winkel

52. Winkel, the plusses
Available online (PDF, flat file)
Open license (CC-BY-SA)
Contextual information
Relations
• Titles  Places
• Titles  Persons
• Titles  Other titles
http://www.archives.gov/research/military/ww2/photos/images/ww2-194.jpg

53. http://2.bp.blogspot.com/_BWzuYwiS6-I/TMgeRsFd3mI/AAAAAAAAElw/3cvgbZSPWcs/s1600/doctor+macro+judy+scared.jpg
Winkel, the minusses
Unstructured data (PDF, flat file)
 Not very machine readable
(unlike CSV, XML, JSON, RDF)
PDF is no (real) open standard
(unlike CSV, XML, JSON, RDF)
No links between
titles  Delpher & KB-cat
No links between
titles, places & persons 
external sources (like Wikipedia)

54. ... but the data sources are
unconnected
(and for 3+4 unstructured & not machine-readable)
To summarize:
a lot of information is available about these WW2
underground newspapers
1. Metadata (KB-cat)
2. Content (full-text, Delpher)
3. Context (Winkel, PDF)
4. Relations: titles  places, persons, other titles (Winkel, PDF)
5. External resources about titles, places and persons

55. http://2.bp.blogspot.com/_BWzuYwiS6-I/TMgeRsFd3mI/AAAAAAAAElw/3cvgbZSPWcs/s1600/doctor+macro+judy+scared.jpg
... making
discovery, understanding & research
of these newspapers (and related places & persons)
more difficult than necessary

56. We can solve all these issues!
Good news!

57. Wikiproject(*) Verzetskranten
Systematically and uniformly describe & link all
1.300 Dutch underground newspapers from WW2
on Dutch Wikipedia
tinyurl.com/verzetskranten (in Dutch)
* https://nl.wikipedia.org/wiki/Wikipedia:Wikiproject, https://en.wikipedia.org/wiki/Wikipedia:Wikiproject

58. From 14  1.300 titles
https://nl.wikipedia.org/wiki/Categorie:Illegale_pers_in_de_Tweede_Wereldoorlog

59. Wikiproject(*) Verzetskranten
Systematically and uniformly describe & link all
1.300 Dutch underground newspapers from WW2
on Dutch Wikipedia
tinyurl.com/verzetskranten (in Dutch)
We need a
database!

60. Build central database
https://www.youtube.com/watch?v=GVDGuCjog_0

61. Build central database
www.youtube.com/watch?v=GVDGuCjog_0
Step 1: Create Excel-sheet with
• Metadata about newspaper (from Winkel PDF)
• Unique Wikipedia article title
• Contextual info, incl. related persons & titles
(from Winkel PDF)
• PPN: unique ID linking newspaper to
KB-catalogue & Delpher

63. Winkel-ID

64. Place of publication

65. Other metadata

66. Title

67. Unique Wikipedia article title
=
<Newspaper title> (verzetsblad, <Place of publication>)

68. • Contextual info
• Related persons
• Related newspaper titles

69. PPN (107123223)
http://opc4.kb.nl/DB=1/
PPN?PPN=107123223

70. http://opc4.kb.nl/DB=1/
PPN?PPN=107123223
PPN (107123223)

71. PPN (107123223)
http://www.delpher.nl/nl/kra
nten/results/index?coll=dddtit
el&cql[]=ppn%3D107123223

72. http://www.delpher.nl/nl/kra
nten/results/index?coll=dddtit
el&cql[]=ppn%3D107123223
PPN (107123223)

73. Build central database
Step 2: Convert Excel into
RDF triplestore
(=special kind of online database anybody can access)
• Steps 1-4 from http://linda-project.eu/linked-
data-primer-2
• Step 4: Vocubulary used = Bibframe
(http://bibframe.org/vocab)

74. Build central database
Step 3: Link to external resources
• Step 5 from http://linda-project.eu/linked-data-primer-2
• DBpedia = machine-readable, structured version of Wikipedia
• DBpedia = hub for linking different data sets on the Web to each
other  Linked Open Data cloud
• Connect persons & places in newspaper database to external
resources via DBpedia

75. Step 1c: Link to external resources
• Step 5 from http://linda-project.eu/linked-data-primer-2
• DBpedia = machine-readable , structured version of Wikipedia
DBpedia allows you to ask sophisticated queries against Wikipedia, and to link
the different data sets on the Web to Wikipedia data
• Connect persons & places in newspaper database to external
resources via DBpedia
http://lod-cloud.net/versions/2010-09-22/lod-cloud_colored.png
Linked Open Data cloud

76. Build central database
Step 3: Link to external resources
• Step 5 from http://linda-project.eu/linked-data-primer-2
• DBpedia = machine-readable, structured version of Wikipedia
• DBpedia = hub for linking different data sets on the Web to each
other  Linked Open Data cloud
• We use DBpdia to connect persons & places in our newspaper
database to information in other databases

77. http://nl.dbpedia.org/page/Huib_Drion
https://nl.wikipedia.org/wiki/Huib_Drion
http://www.dbnl.org/auteurs/auteur.php?id=drio001
http://www.biografischportaal.nl/persoon/41181342

78. Build central database
Added value of Linked Open Data & DBpedia
Software can automatically query for additional
information about places and persons mentioned in
De Winkel that is not available in
• KB-catalogue
• Delpher
• De Winkel

80. Summary: data about 1.300 newspapers
Available online Structured data (RDF-triples)
Open license (CC-BY-SA) Open standard (RDF)
Contextual information Links between titles 
Delpher & KB-cat
Relations Links between titles, places
• Titles  Places & persons  external
• Titles  Persons sources (via DBpedia)
• Titles  Other titles

81. Summary: data about 1.300 newspapers
Available online Structured data (RDF-triples)
Open license (CC-BY-SA) Open standard (RDF)
Contextual information Links between titles 
Delpher & KB-cat
Relations Links between titles, places
• Titles  Places & persons  external
• Titles  Persons sources (via DBpedia)
• Titles  Other titles

82. Summary: data about 1.300 newspapers
Available online Structured data (RDF-triples)
Open license (CC-BY-SA) Open standard (RDF)
Contextual information Links between titles 
Delpher & KB-cat (via PPNs)
Relations Links between places
• Titles  Places & persons  external
• Titles  Persons sources (via DBpedia)
• Titles  Other titles
(PPNs)

83. http://5stardata.info/en/

84. Wikiproject Verzetskranten
Systematically and uniformly describe & link all
1.300 Dutch underground newspapers from WW2
on Dutch Wikipedia
We need a
template!

85. Using an article template we can generate
1.300 uniform and interlinked Wikipedia articles
from the LOD-database
https://c1.staticflickr.com/9/8281/7699231918_11a7356c38_b.jpg

86. LOD-database + article template = Wikipedia article

87. https://nl.wikipedia.org/wiki/De_Geus_onder_studenten_(verzetsblad)

88. https://nl.wikipedia.org/wiki/De_Geus_onder_studenten_(verzetsblad)
Titles  from database

90. Metadata  from database

92. Related persons
 from database

94. Related newspapers
 from database

96. Winkel-ID
 from database

98. Link to full-texts in Delpher
 from database

100. Link to KB-catalogue record
 from database

102. Fixed categories
on WP and Commons

104. Predefined
fixed strings

105. Grey =
• From database
• Predefined fixed strings
 Uniformity between articles guaranteed!

106. All that WP-writers
need to add manually

107. Problem with Delpher
(and KB-catalogue)
Véry little contextual information
about the newspaper(title)s
https://thejungleisneutral.files.wordpress.com/2013/11/lost.jpg

108. Problem with Delpher
(and KB-catalogue)
Véry little contextual information
about the newspaper(title)s
https://thejungleisneutral.files.wordpress.com/2013/11/lost.jpg
The KB can re-use (embed) the
Wikipedia content in its own
websites to tackle this problem

109. https://nl.wikipedia.org/wiki/De_Geus_onder_studenten_%28verzetsblad%29

110. Delpher - search results..
http://www.delpher.nl/nl/kranten/results?coll=dddtitel&cql[]=ppn+any+(107123223)

111. De geus; (onder studenten) was een verzetsblad uit de Tweede Wereldoorlog,
dat vanaf 4 oktober 1940 tot en met 13 juli 1944 …. Lees verder op Wikipedia
Embedded contextual
snippet from Wikipedia
http://www.delpher.nl/nl/kranten/results?coll=dddtitel&cql[]=ppn+any+(107123223)
Delpher - search results..
De geus; (onder studenten) was een verzetsblad uit de Tweede Wereldoorlog,
dat vanaf 4 oktober 1940 tot en met 13 juli 1944 …. Lees verder op Wikipedia

112. Delpher - object presentation
http://resolver.kb.nl/resolve?urn=ddd:010424553:mpeg21:p001

113. Over De Geus onder
studenten
De geus; (onder studenten) was een
verzetsblad uit de Tweede
Wereldoorlog, dat vanaf 4 oktober
1940 tot en met 13 juli 1944 in Den
Haag werd uitgegeven. Het blad
verscheen in 1940, 1941 en 1943
maandelijks, verder onregelmatig in
een oplage tussen de 250 en 8000
exemplaren. Het werd aanvankelijk
gestencild, en vanaf november 1942
gedrukt en de inhoud bestond
voornamelijk uit opinie-artikelen.
Het blad werd uitgegeven door Jan
Drion en Huib Drion, twee Leidse…
Lees verder op Wikipedia
Embedded contextual snippet
from Wikipedia
http://resolver.kb.nl/resolve?urn=ddd:010424553:mpeg21:p001
Delpher - object presentation

114. Suggested reading
• http://www.ted.com/talks/tim_berners_lee_on_the_next_web
20 years ago, Tim Berners-Lee invented the World Wide Web. For his next project, he's building a web for open, linked data
that could do for numbers what the Web did for words, pictures, video: unlock our data and reframe the way we use it
together.
• https://en.wikipedia.org/wiki/Linked_data
Wikipedia article related to the above video
• http://5stardata.info/en/
The 5 stars of Linked Open Data (Tim Berners-Lee)
• http://linda-project.eu/linked-data-primer-2/
Short primer about creating LOD in practice, starting from an Excel sheet
• http://www.programmableweb.com/news/how-linked-data-solved-digital-age-marketing-
problem/analysis/2015/08/31
The figure near the bottom of the first page is a good illustration of the concept of (linked) triples
• https://en.wikipedia.org/wiki/DBpedia
• https://en.wikipedia.org/wiki/Semantic_network
http://www.gettyimages.nl/detail/nieuwsfoto's/three-women-of-the-ats-light-up-together-ats-regulations-nieuwsfotos/3094265

115. Questions?
olaf.janssen@kb.nl - @ookgezellig
tinyurl.com/verzetskranten
http://www.gettyimages.nl/detail/nieuwsfoto's/three-women-of-the-ats-light-up-together-ats-regulations-nieuwsfotos/3094265