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\newblock Vari\'et\'es k\"ahl\'eriennes compactes avec {$c\sb 1=0$}.
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\newblock Geometry of $K3$ surfaces: moduli and periods (Palaiseau, 1981/1982).

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\newblock Existence of minimal models for varieties of log general type, 2006.
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\newblock Le c\^one k\"ahl\'erien d'une vari\'et\'e hyperk\"ahl\'erienne.
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Koji Cho, Yoichi Miyaoka, and Nicholas~I. Shepherd-Barron.
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\newblock In {\em Higher dimensional birational geometry (Kyoto, 1997)},
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\newblock Rational curves on holomorphic symplectic fourfolds.
\newblock {\em Geom. Funct. Anal.}, 11(6):1201--1228, 2001.

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Yi~Hu and Sean Keel.
\newblock Mori dream spaces and {GIT}.
\newblock {\em Michigan Math. J.}, 48:331--348, 2000.
\newblock Dedicated to William Fulton on the occasion of his 60th birthday.

\bibitem{Hu99}
Daniel Huybrechts.
\newblock Compact hyper-{K}\"ahler manifolds: basic results.
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\bibitem{Hu03b}
Daniel Huybrechts.
\newblock Erratum: ``{C}ompact hyper-{K}\"ahler manifolds: basic results''
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\bibitem{Hu03}
Daniel Huybrechts.
\newblock The {K}\"ahler cone of a compact hyperk\"ahler manifold.
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Yujiro Kawamata.
\newblock On the cone of divisors of {C}alabi-{Y}au fiber spaces.
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\bibitem{Kaw07}
Yujiro Kawamata.
\newblock Flops connect minimal models, 2007.
\newblock http://arXiv.org/abs/0704.1013.

\bibitem{FA}
J{\'a}nos Koll{\'a}r, editor.
\newblock {\em Flips and abundance for algebraic threefolds}.
\newblock Soci\'et\'e Math\'ematique de France, Paris, 1992.
\newblock Papers from the Second Summer Seminar on Algebraic Geometry held at
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J{\'a}nos Koll{\'a}r.
\newblock Singularities of pairs.
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\newblock {\em Birational geometry of algebraic varieties}, volume 134 of {\em
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\newblock Cambridge University Press, Cambridge, 1998.
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\newblock The cone of curves of a {$K3$} surface.
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Eduard Looijenga and Chris Peters.
\newblock Torelli theorems for {K}\"ahler {$K3$} surfaces.
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Daisuke Matsushita.
\newblock On fibre space structures of a projective irreducible symplectic
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\newblock {\em Topology}, 38(1):79--83, 1999.

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Shigeru Mukai.
\newblock Symplectic structure of the moduli space of sheaves on an abelian or
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Yoshinori Namikawa.
\newblock Deformation theory of singular symplectic {$n$}-folds.
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\newblock The weight-two {H}odge structure of moduli spaces of sheaves on a
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Kieran~G. O'Grady.
\newblock A new six-dimensional irreducible symplectic variety.
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\bibitem{ogrady}
Kieran~G. O'Grady.
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\newblock Sur la stabilit\'e des sous-vari\'et\'es lagrangiennes des
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\bibitem{W}
Jan Wierzba.
\newblock Contractions of symplectic varieties.
\newblock {\em J. Algebraic Geom.}, 12(3):507--534, 2003.

\bibitem{WW}
Jan Wierzba and Jaros{\l}aw~A. Wi{\'s}niewski.
\newblock Small contractions of symplectic 4-folds.
\newblock {\em Duke Math. J.}, 120(1):65--95, 2003.

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