@incollection{piskorski2013information,
  abstract = {In this chapter we present a brief overview of Information Extraction, which is an area of natural language processing that deals with finding factual information in free text. In formal terms, },
  author = {Piskorski, Jakub and Yangarber, Roman},
  booktitle = {Multi-source, Multilingual Information Extraction and Summarization},
  doi = {10.1007/978-3-642-28569-1_2},
  editor = {Poibeau, Thierry and Saggion, Horacio and Piskorski, Jakub and Yangarber, Roman},
  interhash = {276145faeb3b45461f09f6ae5aabef5e},
  intrahash = {55c1de993e15515d35b68a512088d607},
  isbn = {978-3-642-28568-4},
  language = {English},
  pages = {23-49},
  publisher = {Springer Berlin Heidelberg},
  series = {Theory and Applications of Natural Language Processing},
  title = {Information Extraction: Past, Present and Future},
  url = {http://dx.doi.org/10.1007/978-3-642-28569-1_2},
  year = 2013
}

@article{crestani1997spreading,
  abstract = {This paper surveys the use of Spreading Activation techniques onSemantic Networks in Associative Information Retrieval. The majorSpreading Activation models are presented and their applications toIR is surveyed. A number of works in this area are criticallyanalyzed in order to study the relevance of Spreading Activation forassociative IR.
ER  -},
  author = {Crestani, F.},
  interhash = {3dfe398bb588335ffc562088d5a509de},
  intrahash = {c26c16e0a8036000b788fada656f59dd},
  journal = {Artificial Intelligence Review},
  month = {December},
  number = 6,
  pages = {453--482},
  title = {Application of Spreading Activation Techniques in Information Retrieval},
  url = {http://dx.doi.org/10.1023/A:1006569829653},
  volume = 11,
  year = 1997
}

@article{1159300,
  address = {Piscataway, NJ, USA},
  author = {Kayed, Mohammed and Shaalan, Khaled F.},
  doi = {http://dx.doi.org/10.1109/TKDE.2006.152},
  interhash = {3180af7192c7535d5155630c846eee80},
  intrahash = {234a08916f1fd77df13ea731622333f7},
  issn = {1041-4347},
  journal = {IEEE Transactions on Knowledge and Data Engineering},
  note = {Member-Chia-Hui Chang and Member-Moheb Ramzy Girgis},
  number = 10,
  pages = {1411--1428},
  publisher = {IEEE Educational Activities Department},
  title = {A Survey of Web Information Extraction Systems},
  volume = 18,
  year = 2006
}