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KIT – University of the State of Baden-Wuerttemberg and
National Research Center of the Helmholtz Association
Institute of...
Institute of Applied Informatics and Formal Description Methods2 29.05.2012
MOTIVATION
Basil Ell – Verbalizing SPARQL quer...
Institute of Applied Informatics and Formal Description Methods3 29.05.2012
Motivation
Basil Ell – Verbalizing SPARQL quer...
Institute of Applied Informatics and Formal Description Methods4 29.05.2012
Motivation
Basil Ell – Verbalizing SPARQL quer...
Institute of Applied Informatics and Formal Description Methods5 29.05.2012
Motivation
Basil Ell – Verbalizing SPARQL quer...
Institute of Applied Informatics and Formal Description Methods6 29.05.2012
Motivation
Basil Ell – Verbalizing SPARQL quer...
Institute of Applied Informatics and Formal Description Methods7 29.05.2012
APROACH
Basil Ell – Verbalizing SPARQL queries
Institute of Applied Informatics and Formal Description Methods8 29.05.2012
The pipeline architecture
Basil Ell – Verbaliz...
Institute of Applied Informatics and Formal Description Methods9 29.05.2012
The pipeline architecture
Basil Ell – Verbaliz...
Institute of Applied Informatics and Formal Description Methods10 29.05.2012
The pipeline architecture
Basil Ell – Verbali...
Institute of Applied Informatics and Formal Description Methods11 29.05.2012
The pipeline architecture
Basil Ell – Verbali...
Institute of Applied Informatics and Formal Description Methods12 29.05.2012
The pipeline architecture
Basil Ell – Verbali...
Institute of Applied Informatics and Formal Description Methods13 29.05.2012
Restrictions
Basil Ell – Verbalizing SPARQL q...
Institute of Applied Informatics and Formal Description Methods14 29.05.2012
Restrictions
Basil Ell – Verbalizing SPARQL q...
Institute of Applied Informatics and Formal Description Methods15 29.05.2012
Restrictions
Basil Ell – Verbalizing SPARQL q...
Institute of Applied Informatics and Formal Description Methods16 29.05.2012
Restrictions
Basil Ell – Verbalizing SPARQL q...
Institute of Applied Informatics and Formal Description Methods17 29.05.2012
Example – SPARQL query
Basil Ell – Verbalizin...
Institute of Applied Informatics and Formal Description Methods18 29.05.2012
Example query – graph representation
Basil El...
Institute of Applied Informatics and Formal Description Methods19 29.05.2012
Document structuring – 4 Steps
Basil Ell – Ve...
Institute of Applied Informatics and Formal Description Methods20 29.05.2012
Example – identify main entity
Basil Ell – Ve...
Institute of Applied Informatics and Formal Description Methods21 29.05.2012
Example – identify main entity
Basil Ell – Ve...
Institute of Applied Informatics and Formal Description Methods22 29.05.2012
Example – identify main entity
Basil Ell – Ve...
Institute of Applied Informatics and Formal Description Methods23 29.05.2012
Example – identify main entity
Basil Ell – Ve...
Institute of Applied Informatics and Formal Description Methods24 29.05.2012
Example – identify main entity
Basil Ell – Ve...
Institute of Applied Informatics and Formal Description Methods25 29.05.2012
Example – identify main entity
Basil Ell – Ve...
Institute of Applied Informatics and Formal Description Methods26 29.05.2012
Graph transformation
Idea: Reduce the set of ...
Institute of Applied Informatics and Formal Description Methods27 29.05.2012
Graph transformation
Idea: Reduce the set of ...
Institute of Applied Informatics and Formal Description Methods28 29.05.2012
Example – transformed graph
Basil Ell – Verba...
Institute of Applied Informatics and Formal Description Methods29 29.05.2012
Message creation
Cut graph into independently...
Institute of Applied Informatics and Formal Description Methods30 29.05.2012
Example – messages
Basil Ell – Verbalizing SP...
Institute of Applied Informatics and Formal Description Methods31 29.05.2012
Example – messages
Basil Ell – Verbalizing SP...
Institute of Applied Informatics and Formal Description Methods32 29.05.2012
Example – messages
Basil Ell – Verbalizing SP...
Institute of Applied Informatics and Formal Description Methods33 29.05.2012
Example – messages
Basil Ell – Verbalizing SP...
Institute of Applied Informatics and Formal Description Methods34 29.05.2012
Example – messages
Basil Ell – Verbalizing SP...
Institute of Applied Informatics and Formal Description Methods35 29.05.2012
Document Plan
Basil Ell – Verbalizing SPARQL ...
Institute of Applied Informatics and Formal Description Methods36 29.05.2012
Document Plan
Basil Ell – Verbalizing SPARQL ...
Institute of Applied Informatics and Formal Description Methods37 29.05.2012
Document Plan
Basil Ell – Verbalizing SPARQL ...
Institute of Applied Informatics and Formal Description Methods38 29.05.2012
Document Plan
Basil Ell – Verbalizing SPARQL ...
Institute of Applied Informatics and Formal Description Methods39 29.05.2012
Example - verbalization
Basil Ell – Verbalizi...
Institute of Applied Informatics and Formal Description Methods40 29.05.2012
Example - verbalization
Basil Ell – Verbalizi...
Institute of Applied Informatics and Formal Description Methods41 29.05.2012
Example - verbalization
Basil Ell – Verbalizi...
Institute of Applied Informatics and Formal Description Methods42 29.05.2012
Example - verbalization
Basil Ell – Verbalizi...
Institute of Applied Informatics and Formal Description Methods43 29.05.2012
Example - verbalization
Basil Ell – Verbalizi...
Institute of Applied Informatics and Formal Description Methods44 29.05.2012
Example - verbalization
Basil Ell – Verbalizi...
Institute of Applied Informatics and Formal Description Methods45 29.05.2012
SUMMARY AND FUTURE WORK
Basil Ell – Verbalizi...
Institute of Applied Informatics and Formal Description Methods46 29.05.2012
Summary and Future Work
Summary:
Presented an...
Institute of Applied Informatics and Formal Description Methods47 29.05.2012
Summary and Future Work
Summary:
Presented an...
Institute of Applied Informatics and Formal Description Methods48 29.05.2012
?QUESTIONS
http://km.aifb.kit.edu/projects/sp...
Institute of Applied Informatics and Formal Description Methods49 29.05.2012
REFERENCES
Basil Ell – Verbalizing SPARQL que...
Institute of Applied Informatics and Formal Description Methods50 29.05.2012
References
Basil Ell – Verbalizing SPARQL que...
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SPARTIQULATION - Verbalizing SPARQL queries

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This presentation was given at the International Workshop on Interacting with Linked Data (ILD 2012) co-located with the 9th Extended Semantic Web Conference 2012, Heraklion, and is related the publication of the same title.

Much research has been done to combine the fields of Data-bases and Natural Language Processing. While many works focus on the problem of deriving a structured query for a given natural language question, the problem of query verbalization -- translating a structured query into natural language -- is less explored. In this work we describe our approach to verbalizing SPARQL queries in order to create natural language expressions that are readable and understandable by the human day-to-day user. These expressions are helpful when having search engines that generate SPARQL queries for user-provided natural language questions or keywords. Displaying verbalizations of generated queries to a user enables the user to check whether the right question has been understood. While our approach enables verbalization of only a subset of SPARQL 1.1, this subset applies to 90% of the 209 queries in our training set. These observations are based on a corpus of SPARQL queries consisting of datasets from the QALD-1 challenge and the ILD2012 challenge.

The publication is available at http://www.aifb.kit.edu/images/b/b7/VerbalizingSparqlQueries.pdf

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SPARTIQULATION - Verbalizing SPARQL queries

  1. 1. KIT – University of the State of Baden-Wuerttemberg and National Research Center of the Helmholtz Association Institute of Applied Informatics and Formal Description Metthods (AIFB) www.kit.edu ?uri ?string?states ?population yago:AfricanCountries dbo:capital rdfs:label <1000000 LANG=en optional SPARTIQULATION Verbalizing SPARQL queries Basil Ell, Denny Vrandečić, Elena Simperl International Workshop on Interacting with Linked Data, Extended Semantic Web Conference 2012 28 May 2012
  2. 2. Institute of Applied Informatics and Formal Description Methods2 29.05.2012 MOTIVATION Basil Ell – Verbalizing SPARQL queries
  3. 3. Institute of Applied Informatics and Formal Description Methods3 29.05.2012 Motivation Basil Ell – Verbalizing SPARQL queries SPARQL [QALD 2011] [Haase et al., 2009] [Shekarpour et al., 2011]
  4. 4. Institute of Applied Informatics and Formal Description Methods4 29.05.2012 Motivation Basil Ell – Verbalizing SPARQL queries SPARQL SPARQL [QALD 2011] [Haase et al., 2009] [Shekarpour et al., 2011]
  5. 5. Institute of Applied Informatics and Formal Description Methods5 29.05.2012 Motivation Basil Ell – Verbalizing SPARQL queries SPARQL SPARQLText [QALD 2011] [Haase et al., 2009] [Shekarpour et al., 2011]
  6. 6. Institute of Applied Informatics and Formal Description Methods6 29.05.2012 Motivation Basil Ell – Verbalizing SPARQL queries SPARQL SPARQLText [QALD 2011] [Haase et al., 2009] [Shekarpour et al., 2011]
  7. 7. Institute of Applied Informatics and Formal Description Methods7 29.05.2012 APROACH Basil Ell – Verbalizing SPARQL queries
  8. 8. Institute of Applied Informatics and Formal Description Methods8 29.05.2012 The pipeline architecture Basil Ell – Verbalizing SPARQL queries Document Planner Microplanner Surface Realizer Content determination Document structuring Lexicalization Referring expression generation Aggregation Linguistic realization Surface realization SPARQL Text DP TS [Reiter and Dale, 2000]
  9. 9. Institute of Applied Informatics and Formal Description Methods9 29.05.2012 The pipeline architecture Basil Ell – Verbalizing SPARQL queries Document Planner Microplanner Surface Realizer Content determination Document structuring Lexicalization Referring expression generation Aggregation Linguistic realization Surface realization SPARQL Text DP TS 1. Select the information to communicate 2. Constructing messages and deciding for their ordering and structure [Reiter and Dale, 2000]
  10. 10. Institute of Applied Informatics and Formal Description Methods10 29.05.2012 The pipeline architecture Basil Ell – Verbalizing SPARQL queries Document Planner Microplanner Surface Realizer Content determination Document structuring Lexicalization Referring expression generation Aggregation Linguistic realization Surface realization SPARQL Text DP TS 1. Select the information to communicate 2. Constructing messages and deciding for their ordering and structure 3. Decide which words to use in order to express the content 4. Decide how to refer to an entity 5. Map to linguistic structures [Reiter and Dale, 2000]
  11. 11. Institute of Applied Informatics and Formal Description Methods11 29.05.2012 The pipeline architecture Basil Ell – Verbalizing SPARQL queries Document Planner Microplanner Surface Realizer Content determination Document structuring Lexicalization Referring expression generation Aggregation Linguistic realization Surface realization SPARQL Text DP TS 1. Select the information to communicate 2. Constructing messages and deciding for their ordering and structure 3. Decide which words to use in order to express the content 4. Decide how to refer to an entity 5. Map to linguistic structures 6. Create natural language 7. Add structure to text such as HTML elements [Reiter and Dale, 2000]
  12. 12. Institute of Applied Informatics and Formal Description Methods12 29.05.2012 The pipeline architecture Basil Ell – Verbalizing SPARQL queries Document Planner Microplanner Surface Realizer Content determination Document structuring Lexicalization Referring expression generation Aggregation Linguistic realization Surface realization SPARQL Text DP TS 1. Select the information to communicate 2. Constructing messages and deciding for their ordering and structure 3. Decide which words to use in order to express the content 4. Decide how to refer to an entity 5. Map to linguistic structures 6. Create natural language 7. Add structure to text such as HTML elements [Reiter and Dale, 2000]
  13. 13. Institute of Applied Informatics and Formal Description Methods13 29.05.2012 Restrictions Basil Ell – Verbalizing SPARQL queries SPARQL 1.0 SELECT
  14. 14. Institute of Applied Informatics and Formal Description Methods14 29.05.2012 Restrictions Basil Ell – Verbalizing SPARQL queries SPARQL 1.0 SELECT UNION and GROUP BY queries
  15. 15. Institute of Applied Informatics and Formal Description Methods15 29.05.2012 Restrictions Basil Ell – Verbalizing SPARQL queries SPARQL 1.0 SELECT UNION and GROUP BY queries „Disconnected“ query graphs
  16. 16. Institute of Applied Informatics and Formal Description Methods16 29.05.2012 Restrictions Basil Ell – Verbalizing SPARQL queries SPARQL 1.0 SELECT UNION and GROUP BY queries „Disconnected“ query graphs Regular expressions etc.
  17. 17. Institute of Applied Informatics and Formal Description Methods17 29.05.2012 Example – SPARQL query Basil Ell – Verbalizing SPARQL queries 01 PREFIX dbo: <http://dbpedia.org/ontology/> 02 PREFIX yago: <http://dbpedia.org/class/yago/> 03 PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> 04 PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> 05 PREFIX dbp: <http://dbpedia.org/property/> 06 SELECT DISTINCT ?uri ?string 07 WHERE { 08 ?states rdf:type yago:AfricanCountries . 09 ?states dbo:capital ?uri . 10 ?uri dbp:population ?population . 11 FILTER ( ?population < 1000000 ) . 12 OPTIONAL { ?uri rdfs:label ?string. FILTER (lang(?string) = 'en') } 13 }
  18. 18. Institute of Applied Informatics and Formal Description Methods18 29.05.2012 Example query – graph representation Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable
  19. 19. Institute of Applied Informatics and Formal Description Methods19 29.05.2012 Document structuring – 4 Steps Basil Ell – Verbalizing SPARQL queries Main entity identification Graph trans- formation Message creation Create Document Plan
  20. 20. Institute of Applied Informatics and Formal Description Methods20 29.05.2012 Example – identify main entity Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable Select a variable that is verbalized as subject
  21. 21. Institute of Applied Informatics and Formal Description Methods21 29.05.2012 Example – identify main entity Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable Select a variable that is verbalized as subject
  22. 22. Institute of Applied Informatics and Formal Description Methods22 29.05.2012 Example – identify main entity Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable Select a variable that is verbalized as subject ?string Labels if available of capitals of African countries ... Bad: subject is optional.
  23. 23. Institute of Applied Informatics and Formal Description Methods23 29.05.2012 Example – identify main entity Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable Select a variable that is verbalized as subject ?popu- lation Population < 10^6 of capitals of African countries ... Bad: variable is not selected.
  24. 24. Institute of Applied Informatics and Formal Description Methods24 29.05.2012 Example – identify main entity Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable Select a variable that is verbalized as subject ?states African countries having capitals that have populations < 10^6 ... Bad: variable is not selected.
  25. 25. Institute of Applied Informatics and Formal Description Methods25 29.05.2012 Example – identify main entity Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable Select a variable that is verbalized as subject ?uri Capitals of African countries having population < 10^6 ... Good: Label for main entity is requested.
  26. 26. Institute of Applied Informatics and Formal Description Methods26 29.05.2012 Graph transformation Idea: Reduce the set of message types to simplify verbalization Main entity is transformed into root node Reversal of some edges necessary Basil Ell – Verbalizing SPARQL queries
  27. 27. Institute of Applied Informatics and Formal Description Methods27 29.05.2012 Graph transformation Idea: Reduce the set of message types to simplify verbalization Main entity is transformed into root node Reversal of some edges necessary Basil Ell – Verbalizing SPARQL queries
  28. 28. Institute of Applied Informatics and Formal Description Methods28 29.05.2012 Example – transformed graph Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital - rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable
  29. 29. Institute of Applied Informatics and Formal Description Methods29 29.05.2012 Message creation Cut graph into independently verbalizable parts Filters are stored in VAR messages Basil Ell – Verbalizing SPARQL queries 1 1 Messages (1-9) represent paths, message types are path classes
  30. 30. Institute of Applied Informatics and Formal Description Methods30 29.05.2012 Example – messages Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital - rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable
  31. 31. Institute of Applied Informatics and Formal Description Methods31 29.05.2012 Example – messages Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital - rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable (5) M(RV)*RlV
  32. 32. Institute of Applied Informatics and Formal Description Methods32 29.05.2012 Example – messages Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital - rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable (3) M(RV)*RV (5) M(RV)*RlV
  33. 33. Institute of Applied Informatics and Formal Description Methods33 29.05.2012 Example – messages Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital - rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable (7) M(RV)*RtR (3) M(RV)*RV (5) M(RV)*RlV
  34. 34. Institute of Applied Informatics and Formal Description Methods34 29.05.2012 Example – messages Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital - rdfs:label <1000000 LANG=en optional ?var ?var resource filter selected var variable (7) M(RV)*RtR (3) M(RV)*RV (5) M(RV)*RlV (10) VAR+4 x
  35. 35. Institute of Applied Informatics and Formal Description Methods35 29.05.2012 Document Plan Basil Ell – Verbalizing SPARQL queries constraints requests modifiers DP 1 2 3
  36. 36. Institute of Applied Informatics and Formal Description Methods36 29.05.2012 Document Plan Basil Ell – Verbalizing SPARQL queries constraints requests modifiers DP 1 2 3 Constraits for main entity, e.g. its class, having population < 10^6
  37. 37. Institute of Applied Informatics and Formal Description Methods37 29.05.2012 Document Plan Basil Ell – Verbalizing SPARQL queries constraints requests modifiers DP 1 2 3 Requested information, e.g. its name Constraits for main entity, e.g. its class, having population < 10^6
  38. 38. Institute of Applied Informatics and Formal Description Methods38 29.05.2012 Document Plan Basil Ell – Verbalizing SPARQL queries constraints requests modifiers DP 1 2 3 Modifiers, e.g. LIMIT, ORDER BY ... Requested information, e.g. its name Constraits for main entity, e.g. its class, having population < 10^6
  39. 39. Institute of Applied Informatics and Formal Description Methods39 29.05.2012 Example - verbalization Basil Ell – Verbalizing SPARQL queries ?uri ?states yago:AfricanCountries dbo:capital - M(RV)*RtR (cons)
  40. 40. Institute of Applied Informatics and Formal Description Methods40 29.05.2012 Example - verbalization Basil Ell – Verbalizing SPARQL queries ?uri ?states yago:AfricanCountries dbo:capital - M(RV)*RtR Capitals of African countries (cons)
  41. 41. Institute of Applied Informatics and Formal Description Methods41 29.05.2012 Example - verbalization Basil Ell – Verbalizing SPARQL queries ?uri ?states yago:AfricanCountries dbo:capital - M(RV)*RtR Capitals of African countries ?uri ?population <1000000 M(RV)*RV (cons) (cons)
  42. 42. Institute of Applied Informatics and Formal Description Methods42 29.05.2012 Example - verbalization Basil Ell – Verbalizing SPARQL queries ?uri ?states yago:AfricanCountries dbo:capital - M(RV)*RtR Capitals of African countries ?uri ?population <1000000 M(RV)*RV that are having populations that are less than 1000000 (cons) (cons)
  43. 43. Institute of Applied Informatics and Formal Description Methods43 29.05.2012 Example - verbalization Basil Ell – Verbalizing SPARQL queries ?uri ?states yago:AfricanCountries dbo:capital - M(RV)*RtR Capitals of African countries ?uri ?population <1000000 M(RV)*RV that are having populations that are less than 1000000 ?uri ?stringrdfs:label LANG=en optional M(RV)*RlV (cons) (cons) (req)
  44. 44. Institute of Applied Informatics and Formal Description Methods44 29.05.2012 Example - verbalization Basil Ell – Verbalizing SPARQL queries ?uri ?states yago:AfricanCountries dbo:capital - M(RV)*RtR Capitals of African countries ?uri ?population <1000000 M(RV)*RV that are having populations that are less than 1000000 ?uri ?stringrdfs:label LANG=en optional M(RV)*RlV where available their English labels.and (cons) (cons) (req)
  45. 45. Institute of Applied Informatics and Formal Description Methods45 29.05.2012 SUMMARY AND FUTURE WORK Basil Ell – Verbalizing SPARQL queries
  46. 46. Institute of Applied Informatics and Formal Description Methods46 29.05.2012 Summary and Future Work Summary: Presented an approach for explaining SPARQL SELECT queries in natural language Schema-agnostic Basil Ell – Verbalizing SPARQL queries
  47. 47. Institute of Applied Informatics and Formal Description Methods47 29.05.2012 Summary and Future Work Summary: Presented an approach for explaining SPARQL SELECT queries in natural language Schema-agnostic Directions for future work: Tackle challenges in the two missing pipeline components Exploitation of linguistic features of labels Evaluation Basil Ell – Verbalizing SPARQL queries
  48. 48. Institute of Applied Informatics and Formal Description Methods48 29.05.2012 ?QUESTIONS http://km.aifb.kit.edu/projects/spartiqulator/ Basil Ell – Verbalizing SPARQL queries ?uri ?string?states ?population yago:AfricanCountries dbo:capital rdfs:label <1000000 LANG=en optional The work presented here is supported by the European Union's 7th Framework Programme (FP7/2007-2013) under Grant Agreement 257790. http://bit.ly/KGuDTL
  49. 49. Institute of Applied Informatics and Formal Description Methods49 29.05.2012 REFERENCES Basil Ell – Verbalizing SPARQL queries
  50. 50. Institute of Applied Informatics and Formal Description Methods50 29.05.2012 References Basil Ell – Verbalizing SPARQL queries S. Shekarpour, S. Auer, A.-C. Ngonga Ngomo, D. Gerber, S. Hellmann, and C. Stadler. Keyword-driven SPARQL Query Generation Leveraging Background Knowledge. In International Conference on Web Intelligence, 2011. E. Reiter and R. Dale. Building Natural Language Generation Systems. Natural Language Processing. Cambridge University Press, 2000. P. Haase, D. M. Herzig, M. Musen, and D. T. Tran. Semantic Wiki Search. In L. A. P. et al., editor, 6th Annual European Semantic Web Conference, ESWC2009, Heraklion, Crete, Greece, volume 5554 of LNCS, pages 445- 460. Springer Verlag, Juni 2009. QALD 2011: http://www.sc.cit-ec.uni-bielefeld.de/qald-1

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