Package natbib Error: Bibliography not compatible with author-year citations.
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l.30 ...mandNAT@force@numbers{}NAT@force@numbers

Check the bibliography entries for non-compliant syntax,
or select author-year BibTeX style, e.g. plainnat

@book{adams1995hitchhiker,
  title={The Hitchhiker's Guide to the Galaxy},
  author={Adams, D.},
  isbn={9781417642595},
  url={http://books.google.com/books?id=W-xMPgAACAAJ},
  year={1995},
  publisher={San Val}
}
@book{MillerJohnson-Laird1976,
  title = {{Language and perception}},
  author = {George A. Miller, Philip N. Johnson-Laird},
  url={http://psycnet.apa.org/index.cfm?fa=search.displayRecord&uid=1987-97426-000},
  year = {1976},
  publisher = {Belknap Press}
  note = "Cambridge, MA, England: Belknap Press Language and perception. (1976). viii 760 pp."
}
@misc{ApacheOpenNLP2015,
  title={{OpenNLP, Apache}},
  howpublished = url{https://opennlp.apache.org/},
  year = {2015},
  note="[Online; último acesso em 09 de agosto de 2015]"
}

@misc{GeorgeAMiller-Rev1993,
  author = {George A. Miller, Richard Beckwith, Christiane Fellbaum, Derek Gross, and Katherine Miller},
  title = {{Introduction to WordNet: An On-line Lexical Database}},
  howpublished = "url{http://wordnetcode.princeton.edu/5papers.pdf}",
  year = {1993},
  note = "[Online; último acesso em 08 de agosto de 2015]"
}