Metadata Interoperability

1
Metadata Interoperability

• Lina Bountouri
• Ionian University
• February 2008

2
??ad??t??

• ?????? f???a? p????f???s??
• ????? ded?µ????
• 2005 The Indexable Web is 19.1 billion
  documents Yahoo, 2005
• ??????e? ?µ?de? ???st??
• ??????e? a????e? p????f???s??
• ?p?t??esµa ??a??a?a ?a? pa??????a d?s???? ?
  d??at?t?ta ap?te?esµat???? p??sßas??

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?p?peda ete?????e?a? ded?µ????

• ?te?????e?a S?st?µ?t?? (hardware, operating
  systems, networking protocols ?t?)
• ?te?????e?a st? S??ta?? (query languages,
  encodings etc )
• ?te?????e?a S??µ?t?? (data models, data schemas
  etc)
• S?µas???????? ?te?????e?a (semantic conflicts)

???ß??µata st?? p??sßas?
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????????s? ded?µ????

• ???a?a p??sßas? se s??????? a?t???µ?? p???? ??
  e??a?? s?????
• ??a s?st?µa ????????s?? ded?µ???? p????e? t??
  p??sßas? ?a? t?? ap?te?esµat??? a???t?s?, ef?s??
• s??d???e? ded?µ??a ap? d?af??et???? p????,
  d?af??et??? s?st?µata, ta ?p??a e??a?
  µ??te??p???µ??a µe d?af??et??? s??µata
• pa???e? st??? ???ste? ??a ?µ??e??p???µ??? s?????
  ap?te?esµ?t??
• ?a??de??µa S?st?µata ??aµes???ß?s?? (Mediated
  Systems)
• ta ded?µ??a ???????????ta? µ?sa ap? µ?a e???????
  ?a?????? ??? t?? ep?µ????? p???? (t? ?a??????
  s??µa ? s??µa d?aµes???ß?s?? (mediated schema or
  global schema))
• ? ???st?? ??t?e? t? ?a?????? s??µa ?a? t? e??t?µa
  µetas??µat??eta? se e??t?µa a?a?????s?µ? ap? ???e
  t?p??? p??? (reformulation step)

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???t?µa ???st?
S??µa ??aµes???ß?s??
?etas??µat?sµ?? e??t?µat?? p??? t?? t?p??? p???
??p??? ????
??p??? ????
??p??? ????
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?p??t?s? st? ???st?
???p???s? ap?te?esµ?t??
S??µa ??aµes???ß?s??
?p??t?s? t?p???? p????
??p??? ????
??p??? ????
??p??? ????
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????????s? ded?µ????

• ?? ???ste? e?d?af????ta? ??a e??p???µ??e?
  d?ad??µ??
• ????????s? ded?µ???? (a) de ??e???eta? ?a
  ????????? p?? ß??s???ta? ta p?a?µat??? ded?µ??a,
  ?a? (b) ?a ????? p??sßas? se ???e µ?a p???
  ????st? ??a ?a ta a?a?t?s???
• ?? p?????se?? e??? s?st?µat?? ????????s??
  ded?µ???? af?????
• ?? ßa?µ? a?t?µat?p???s?? t?? d?ad??as?a? t??
  ????????s??
• ?? d?at???s? t?? s?µas??????a? ???e p????

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S?µas???????? ????????s? ?ed?µ????

• ?a???sµ??? ?st?? S?µas????????? ?st??
• ???sµ?? ??ad??as?a t?? ???s?? e????????????
  a?apa?ast?se?? t?? ded?µ???? ?a? t?? s??se?? t???
  µe st??? t?? e???e??? t?? s?µas?????????
  ete?????e?a?
• ??e? te???????e? ??a t?? a?apa??stas? ???s?? ?a?
  t?? a???p???s? t??, p.?. ??t?????e?

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??t?????a

• ??a t?p??? (formal), ?at?????µat??? (explicit)
  p??d?a??af? µ?a? d?aµ???asµ???? (shared)
  e???????????? a?apa??stas?? (conceptualization)
• Artificial-intelligence and Web researchers have
  co-opted the term for their own jargon, and for
  them an ontology is a document or file that
  formally defines the relations among terms. The
  most typical kind of ontology for the Web has a
  taxonomy and a set of inference rules.

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?? ??t?????e? st? S?µas???????? ????????s?
?ed?µ????

• ???a??sµ?? d?a?e?t???????t?ta?
• ??t?????a ?? s??µa d?aµes???ß?s?? st?? ????????s?
  ded?µ???? (Ontology-based Integration scenarios)
• ????p???e? s??se?? e??? ?eµat???? ped???
• ??st??? f??µa??sµ? e?a???? s?µpe?asµ?t??
  (reasoning)
• ???pt??? ??t??????? ??a ??a ?eµat??? ????,
  e??????????? a?apa??stas? e??? t?µ?a (Domain
  Ontologies), p.?. CIDOC ?a? ABC ??a p???t?st???
  pe??e??µe??,
• ???????µµ?s? (alignment) e?????? ?a? ????

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?etaded?µ??a

• The word is half Latin and half Greek. No good
  can come of it!
• ?a µetaded?µ??a e??a? ?? p????f???e?
  p??sd???????? ?a? ta?t????? p???? / a?t??e?µe?a,
  ?p?????? se d??f??e? µ??f?? ?a? st???? t??? e??a?
  ?a ?a?????? p?????a ep?peda pe????af??, a????e?
  te?µ????s?? ?a? p??sßas??

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Real World Example

• ?d??? st? d??µ? ??a t? sp?t?...
• ????? ??a f?????...
• ???p? taµp??e? ?atast?µ?t??...
• ??a????? µ?a taµp??a p?? ???fe? F?????? ?e??t??
• ?a????? ?a? p?? ?a ????s?...
• ???a? ????? t? ß??d? (0900 µ.µ.)...
• ???a? ??e?st?...

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Real World Example

• Ta µe e??e d?e??????e? a? ? taµp??a ????afe
  ?e?t????e? ??e? ?atast?µ?t??...
• S?µp??asµa 1 ta µetaded?µ??a e??a? pa?t?? ?a?
  µa? ß?????? ?a ß???µe t?? p????f???a p??
  ??e?a??µaste!
• S?µp??asµa 2 de? e??a? p??ta p???? ?? p??? t??
  a????e? p????f???s?? p?? ?a??pt???!
• S???? ??a p????f???a?? s?st?µa de d?aß??e?
  taµp??e?, d?aß??e? ?µ?? d?µ?µ???, µ??a????af?µ???
  p????f???a. G?a pa??de??µa, µ?sa ap? ??a d??t?a??
  t?p? p?? ?a pa?e??e a?a??t?s? ??a ta ?atast?µata
  e?t?? ?????? ?a? ta ?????? t???, ?a µp????saµe ?a
  e??aµe p??e? t?? p????f???e?

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?etaded?µ??a

• G?a ??a word file st? PC ??t??? a??e???,
  d?µ???????, te?e?ta?a t??p?p???s?, ?µe??µ???a
  d?µ??????a?, t?p??es?a st? d?s?? ?t?
• ??? ???t??? pa?ade??µata st?? ep?st?µ??a t??
  p????f???s??
• G?a ??a CD ??t???, s????t??, t?a???d?a,
  t?a???d?st??, st????????, µ??s???? pa?a?????,
  ??s? st? ??f? ?/?a? URL, e?d?? µ??s???? ?t?
• G?a ??a ????af? t?? d?µ?s??? t?µ?a tµ?µa /
  d?e????s? ?t? p?? t? pa???a?e, a???µ??
  p??t???????, ?p???af?? ?pe??????, ??µ??
  d??ta?µa p?? ????e? t? d?µ??????a t??,
  ape?????µe?? ????? / ?p??es?a ?t?

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?etaded?µ??a

• ?e????af? ?a? te?µ????s? p???????? t?p?? ??????
  d?µ??????a ?a? ???s? s???e???µ???? s??µ?t??
  pe????af?? se d?e???? ?a? e????? ep?ped?
• GILS, GovML, AGLS, eGMS ?t? ??a ??ße???t???
  p????f???a (e?e??? a??e?a)
• Encoded Archival Description ??a ta a?e?e??? (?a?
  ?µ?-e?e???) a??e?a
• ???f??a MARC ??a p??????? t?p?? ????? p??
  d?at??eta? ap? ß?ß?????????µ??? s?st?µata
• VRA ??a e????e? ??????

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?etaded?µ??a

• ?????? se e??p???µ??? p??sßas? se ete???e???
  ?????
• G?a pa??de??µa ????? p???t?st???? ?d??µ?t??
  (???e?a, ??ß??????e? ?a? ???se?a) ß??pe ta
  d??f??a ???a p?? ??e? ???µat?d?t?se? ? ???????a
  t?? ?????f???a? µe safe?? ?d???e? ???p???s?? ??a
  a????t?, d?a?e?t??????? pe??e??µe??

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??a?e?t???????t?ta ?etaded?µ????

• ? s?µßat?t?ta a??µesa se d?? ? pe??ss?te?a
  s??µata µetaded?µ????
• ?e p?a?t????? ?????, ? d?a?e?t???????t?ta
  µetaded?µ???? a?t??at?pt???e? t?? ??a??t?ta e???
  s?st?µat?? ?a s?s?et??e? t?? e??????????? (?a?
  ??? µ???) p?e??? e??? s??µat?? µetaded?µ???? µe
  ??a ???? s??µa

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??a?e?t???????t?ta ?etaded?µ????

• ?a µetaded?µ??a ???p?????ta? µe????? f???? µe
  t??p? p?? de? ta ?a??st? d?a?e?t???????
• ?? safe?? ???sµ?? t?? s?µas??????a? t?? ped???
• ?a??asµ??? ???s? ped???
• ?as??? ???ß??µa There are nearly as many types
  of metadata as there are digital collections!!!
• Application Profiles (?)

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??a?e?t???????t?ta ?etaded?µ????

• Metadata element (ped?a µetaded?µ????) ????e?
  µ?a a??et? abstract a??? pa???a a?t? saf? ?????a
  ??a t? ?a?a?t???sµ? ded?µ????. G?a pa??de??µa, t?
  ped?? "Creator" st? DC ????e? t?? p??t?
  p?e?µat??? ?pe?????t?ta ??a t? d?µ??????a t??
  pe??e??µ????
• Metadata element instance (st??µ??t?pa t?? ped???
  t?? µetaded?µ????) ????e? ??a s???e???µ???
  s????? ded?µ???? µ?sa st? ped?? ?a? s?µf??a µe
  t?? ?????a t?? pe??e??µ???? t?? ped??? (metadata
  element). G?a pa??de??µa, t? instance t?? ped???
  Creator ??a a?t? t?? pa???s?as? e??a? ???a
  ?p???t????

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??a?e?t???????t?ta ?etaded?µ????

• Metadata Schema (s??µa µetaded?µ????) ????e? ??a
  s????? saf?? ped??? µetaded?µ???? (sa? a?t? p??
  a?af??aµe EAD, DC, GILS ?t?)
• Metadata schema instance (st??µ??t?pa t??
  s??µat?? t?? µetaded?µ????) ????e? ??a
  s???e???µ??? s????? ded?µ???? p?? e??a? s?µf??a
  µe t? s??µa µetaded?µ???? ?a? t?? e?????? t??
  ped??? t??. G?a pa??de??µa, ??a ta µetaded?µ??a
  ??a a?t? t?? pa???s?as? pe?????f??ta? µe ta
  instances e??? s??µat??, p.?. t?? DC

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???a??sµ?? d?a?e?t???????t?ta?

• Se ?e????? ??aµµ?? d?? ßas???? p??se???se??
• ???sµ?? e??? ?????? p??t?p?? (?p?? ??e? ???e? st?
  ???? t?? ß?ß???????? µe ta d??f??a MARC ())
• ??µ??????a metadata gateways ?? ?p??e?
  µetat??p??? s???e???µ??a s??µata µetaded?µ???? se
  ???a s??µata
• ?µfas? st? de?te?? p??s????s?

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???a??sµ?? d?a?e?t???????t?ta?

• Sta p?a?s?a t?? de?te??? p??s????s??
  a???p?????ta? d??f??a e??a?e?a, ?p??
• Interoperable core ??a s??µa µetaded?µ????
  (s?et??? ap??, s?????? t? DC) a???p??e?ta? ??
  ?e?t???? s?µe?? a?af???? ?a? ?????ta? s?s?et?se??
  ap? ta d??f??a µetaded?µ??a p??? a?t?
• Crosswalks ???sµ?? s?s?et?se?? t?? ped??? e???
  s??µat?? µetaded?µ???? p??? ??a ????
• Ontology-based integration ????????s? ded?µ????
  µe t? ???s? ??t???????, ?p?? µ?a ??t?????a
  a???p??e?ta? ?? ?e?t???? s?µe?? a?af???? ?a?
  ?????ta? s?s?et?se?? ap? ta d??f??a µetaded?µ??a
  p??? a?t??

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?? e?et????µe eµe??

• Crosswalks ap? a??e?a?? µetaded?µ??a (p.?. EAD)
  p??? ß?ß?????af??? µetaded?µ??a (p.?. MODS)
• S?s?et?se?? ap? µetaded?µ??a p?? af????? t? ????
  t?? cultural/memory institutions p??? t??
  ??t?????a te?µ????s?? p???t?sµ???? p????f???a?
  CIDOC CRM

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Crosswalks

• ??a ped?? e??? s??µat?? ?a a?t?st???e? se ??a ?
  pe??ss?te?a ped?a e??? ????? s??µat??
• G?a pa??de??µa t? ped?? did/unittitle t?? EAD
  a?t?st???e? st? ped?? titleInfo/title t?? MODS
• ?da???? ??a pe?????sµ??? a???µ? s??µ?t??
  µetaded?µ???? ?a? ?????? ??a ?????? t?p????
  a?a???? (p.?. ?etat??p? se MARC ??a p??sßas? µ?s?
  t?? OPAC)
• ?e d??f??a e??a?e?a, p.?. MarcEdit ?a? ???s?
  stylesheets

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Crosswalks

• ???sµ?? p??????? s??se?? µ?sa ap? µ?a s?s??t?s?
• 1 ?????
• 1 ?a???a
• ??µ? ?e?a???a
• ??µ? Se???
• ????d?? pe?????sµ???? ap?te?esµat???t?ta?, e?d???
  ?ta? a??????ta? ta eµp?e??µe?a µetaded?µ??a

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S?s?et?se?? µetaded?µ???? µe ??t?????e?

• ??de??t??? pa??de??µa
• ??????µe t? CIDOC ?? ??t?????a? d?aµes???ß?s?? se
  ??a se????? s?µas????????? ????????s??, µe t??
  ?p??a s?s?et????ta? d??f??a s??µata µetaded?µ????
• EAD p??? CIDOC
• Encoded Archival Description ???a? t? d?e????
  s??µa µetaded?µ???? ??a t?? pe????af? a??e???, t?
  ?p??? d?at??e? t?? ?e?a???a t?? a??e??? ?a?
  de???e? t? pe??e??µe?? t?? pe????af???? ?d????
  t?? a??e??? (e??a?e?a ??e??a?)
• CIDOC Conceptual Reference Model (CRM) pa???e?
  ???sµ??? ?a? d?µ? ??a t?? pe????af? t??
  (???sµ???? ?a? ?p?????µe???) e?????? ?a?
  s??se?? p?? ???s?µ?p?????ta? st?? te?µ????s? t??
  p???t?st???? ???????µ???

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S?s?et?se?? µetaded?µ???? µe ??t?????e?

• G?at? ???s?µ?p??????e t? CIDOC ?? µes??aß?t?? t??
  µetaded?µ????
• ???ad??? ??t?????a ??a p????f???a p?? p?????eta?
  ap? a??e?a, ß?ß??????e? ?a? µ??se?a µ???? st??µ??
  se d?e???? ep?ped?. (???t??p? ?a a????????µe
  d?e??? p??t?pa ?a? ?d???e? ???p???s??. ???µa ?a?
  a? de µa? ?a??pt??? p?????, µa? pa?????? ?? ??a
  ßa?µ? s?µßat?t?ta d??t? ???s?µ?p?????ta? ?a? ap?
  ??????!)

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S?s?et?se?? µetaded?µ???? µe ??t?????e? ????d??
?a? p??ß??µata

• Path-Oriented Approach
• Mappings ??a s?s??t?s? ap? t? s??µa p???? (p.?.
  EAD) p??? t? s??µa st???? (p.?. CIDOC) µetat??pe?
  ped?a ap? t? p??t? s??µa sta ?????a a?t?st???a
  ped?a t?? s??µat?? st????
• ?e??d?????a ??a mappings ?et?f?as? t?? d?ad??µ??
  t?? µetaded?µ???? p??? ta s?µas????????
  a?t?st???a CIDOC µ???p?t?a

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S?s?et?se?? µetaded?µ???? µe ??t?????e? ????d??
?a? p??ß??µata

• ??a µ???p?t? CIDOC ??e? t? µ??f?
  entity-property-entity, ??a pa??de??µa
• E22 (Man Made Object)-P108(has produced/was
  produced by)- E12 (Production Event)-P14(carried
  out by/performed)-E39(Actor) d??????ta? ?t? ??a?
  d?µ??????? (Actor, E39) ?at? t? d????e?a e???
  ?e????t?? d?µ??????a? (E12) d?µ??????se ??a
  f?s??? a?t??e?µe?? p?? p?????eta? ap? a????p???
  d?ast????t?ta, p.?. ??a a??e?? (Man Made Object,
  E22)

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S?s?et?se?? µetaded?µ???? µe ??t?????e? ????d??
?a? p??ß??µata

• ??a µ???p?t? µetaded?µ???? (?????? XML) ????eta?
  ?? µ?a a???????a ap? st???e?a, ?p?-st???e?a ?t?,
  ?e?????ta? ap? t?? a????? ??µß? (st???e??) t??
  s??µat?? ?a? s??e?????ta? µe ta ?p?-st???e?a p??
  eµp?????ta? ???e f??? d?a????sµ??a µe t? s?µß???
  (/), ??a pa??de??µa
• /ead/archdesc/did/origination/persname, t? ?p???
  d????e? t? ???µa t?? d?µ??????? t?? a??e?a???
  pe????af??

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S?s?et?se?? µetaded?µ???? µe ??t?????e? ????d??
?a? p??ß??µata

• ? µ???d?? e??a? ?at?????? ef?s?? ta µetaded?µ??a
  ?a? ?? ??t?????e? ??d???p????? t?? p????f???e?
  µ?s? µ???pat??? (paths)
• ?a??de??µa p?? ap?de????e? t? ???s? t?? µe??d??
  ?d?? st???e?? (???µa st???e???) se d?af??et???
  µ???p?t? ???e f???, µe d?af??et??? s?µas??????a
  se ???e pe??pt?s?
• /ead/archdesc/did/originator/corpname
• /ead/archdesc/did/repository/corpname

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S?s?et?se?? µetaded?µ???? µe ??t?????e? ????d??
?a? p??ß??µata

• ?etaded?µ??a ?a? ??t?????e? d?af??et???? s??p??
  ?a? ?e?t?????a
• ?etaded?µ??a pe????af?, ta?t?p???s?, d?e??????s?
  p??sßas??, ???s? ?a? d?a?e???s? p????
• ??t?????e? conceptualization s???e???µ????
  ????? ?a? ?eµ?t??, de? pe???aµß????? ped?a ??a
  pe????af? a??? ?????e? e??? ????? ?a? t?? s??se??
  µeta?? t???
• ??af??et???? t??p?? ???sµ?? t?? s?µas??????a?, ??
  ??t?????e? ????? d?µ??? st???e?a ??a?? ?a
  e?f??s??? p???s?a s?µas??????a ?a? s??se??
  a??µesa st?? s?µas?e?, ta µetaded?µ??a st??
  pa???sa f?s? ???.

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S?s?et?se?? µetaded?µ???? µe ??t?????e? ????d??
?a? p??ß??µata

• Event orientation
• ?etaded?µ??a st??e???? st? pe????af?µe??
  a?t??e?µe?? (p.?. a??e??, ????? ap? pe???d???). ?
  ??t?????a CIDOC ßas??eta? se ?e????ta ?a?
  d?ast????t?te? (event based).
• ?as???? ?????e? t?? ??t?????a? e??a? ta ?e????ta
  / d?ast????t?te? ?a? ? pa???s?a ????? ??t?t?t??
  ?p?? Actors, Dates, Places, Objects, etc, apa?te?
  s???? t? s?µµet??? t??? se ??a ?e????? ? µ?a
  d?ast????t?ta
• Wrapper elements
• ?a pe??ss?te?a XML µetaded?µ??a (p.?. EAD, TEI
  ?a? MODS) ap?te????ta? ap? p???? wrapper
  st???e?a (p.?. ltdidgt st? EAD) ta ?p??a
  ?µad?p????? s?et???? p????f???e?, a??? de? ?????
  s?µas???????? a??a
• ?e? ta a???p????µe st? mapping

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S?s?et?se?? µetaded?µ???? µe ??t?????e?
?a??de??µa

• ??a EAD ????af? ap?te?e?ta? ap? ta µetaded?µ??a
  t?? ?d??? t?? e????f?? st???e?? lteadheadergt ?a?
  ap? ta µetaded?µ??a t?? a??e??? (a??e?a??
  pe????af?) st???e?? ltarchdescgt
• ? a??e?a?? pe????af? µ?s? t?? CIDOC ????eta?
  µ?sa ap? t?? e??? ?????e?
• E31 (Document) ?a? E33 (Linguistic Object),
  d??????ta? ?t? ? a??e?a?? pe????af? e??a? ??a
  ?e?µe?? t? ?p??? te?µ?????e? ??a a??e??
• E22 (Man-Made Object), d??????ta? ?t? t? a??e??
  e??a? ??a f?s??? a?t??e?µe?? t? ?p??? p?????e ap?
  a????p??? d?ast????t?ta
• E73 (Information Object) ?a? E33 (Linguistic
  Object), ?p?? ?? ???se?? a?af????ta? se
  a?t??e?µe?a ta ?p??a pe???aµß????? t?? a????p???
  µ??µ? ?a? de? e?a?t??ta? ap? ?a???a f?s??? µ?s?
  (physical carrier)
• /ead/archdesc E31 (Document), E33(Linguistic
  Object)-P70 (documents/is documented in)-E22
  (Man-Made Object)-P128 (carries/is carried
  by)-E73 (Information Object), E33 (Linguistic
  Object)

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??ß?????af?a

• Christophe Blanchi and Jason Petrone.
  Distributed Interoperable Metadata Registry
  D-Lib Magazine Vol.7 No. 12 December, 2001.
  http//www.dlib.org/dlib/december01/blanchi/12bla
  nchi.html
• Conrad Taylor. Metadatas many meanings and uses.
  http//www.ideography.co.uk/briefings/pdf/PB_meta
  data.pdf
• Lorcan Dempsey. Network Resource Discovery a
  European Library Perspective. In Libraries,
  networks and Europe a European networking study.
  Neil Smith (ed). London British Library Research
  Development Department, 1994.
  http//www.lub.lu.se/UB2proj/LIS_collection/lorca
  n.html
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