Différencier des références bibliographiques

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@ARTICLE{Vickrey1961,
AUTHOR = {W. Vickrey},
TITLE = {Counterspeculation, auctions and sealed tenders},
JOURNAL = {Journal of Finance},
YEAR = {1961},
VOLUME = {16},
PAGES = {8--37},
}
@BOOK{Dodgson,
AUTHOR =    {Lewis Carroll},
TITLE =     {The Hunting of the Snark},
YEAR =      {1876},
PUBLISHER = {Macmillan},
LOCATION = {London}
}
@BOOK{Lear,
AUTHOR = {Edward Lear},
TITLE = {Les Sept familles du lac Pipple-Popple},
TITLEADDON = {(The History of the seven families of the lake Pipple-Popple)},
TRANSLATOR = {Simone Lamblin},
PUBLISHER = {Gallimard},
LOCATION = {Paris},
YEAR = {1978},
EDITION = {2},
}
@online{nonsense,
    title = {International Owl \& Pussycat Day, 12 May},
year = 2011,
url = {https://teachingnonsenseinschools.wordpress.com},
urldate = {2010-09-30}
}
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Première référence \cite{Vickrey1961}.

Sur la toile : \cite{nonsense}.

Deux livres indispensables : \cite{Lear,  Dodgson}.

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