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@book{A01,
  title={Introduction to Information Retrieval},
  author={Manning, Christopher D. and Raghavan, Prabhakar and Sch{\"u}tze, Hinrich and others},
  year={2008},
  publisher={Cambridge University Press Cambridge}
}
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This is just a text\footnote{\citealp[cf.][Pp.~94-23]{A01}}.

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