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\newblock Del {P}ezzo surfaces of degree 6 over an arbitrary field.
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M.~Bolognesi, F.~Russo, and G.~Staglian\`o.
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\newblock Del {P}ezzo surfaces of degree 6.
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J.L. Colliot-Th\'el\`ene, N.A. Karpenko, and A.S. Merkurjev.
\newblock Rational surfaces and the canonical dimension of the group {${\rm
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\newblock {\em Algebra i Analiz}, 19(5):159--178, 2007.
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\newblock Ideals associated to deformations of singular plane curves.
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\bibitem[Gro68]{Gro}
Alexander Grothendieck.
\newblock Le groupe de {B}rauer. {III}. {E}xemples et compl\'ements.
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Daniel~R. Grayson and Michael~E. Stillman.
\newblock Macaulay2, a software system for research in algebraic geometry.
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\newblock Complete linear systems on rational surfaces.
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\newblock Some rational cubic fourfolds.
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\bibitem[Has00]{Has00}
Brendan Hassett.
\newblock Special cubic fourfolds.
\newblock {\em Compositio Math.}, 120(1):1--23, 2000.

\bibitem[Has16]{Has16}
Brendan Hassett.
\newblock Cubic fourfolds, {K}3 surfaces, and rationality questions.
\newblock In {\em Rationality problems in algebraic geometry}, volume 2172 of
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\bibitem[Hom80]{Homma}
Yuko Homma.
\newblock Projective normality and the defining equations of ample invertible
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\newblock {\em Natur. Sci. Rep. Ochanomizu Univ.}, 31(2):61--73, 1980.

\bibitem[Huy17]{huybrechts}
Daniel Huybrechts.
\newblock The {K}3 category of a cubic fourfold.
\newblock {\em Compos. Math.}, 153(3):586--620, 2017.

\bibitem[Kap09]{Kap}
Grzegorz Kapustka.
\newblock Primitive contractions of {C}alabi-{Y}au threefolds. {II}.
\newblock {\em J. Lond. Math. Soc. (2)}, 79(1):259--271, 2009.

\bibitem[KT17]{KT}
Maxim Kontsevich and Yuri Tschinkel.
\newblock Specialization of birational types, 2017.
\newblock \texttt{arXiv:1708.05699}.

\bibitem[Kuz17]{Kuz17}
Alexander Kuznetsov.
\newblock Derived categories of families of sextic del {P}ezzo surfaces, 2017.
\newblock \texttt{ arXiv:1708.00522}.

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Ju.~I. Manin.
\newblock Rational surfaces over perfect fields.
\newblock {\em Inst. Hautes \'Etudes Sci. Publ. Math.}, (30):55--113, 1966.
\newblock English translation: American Mathematical Society Translations, Ser.
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\newblock Triple covers in algebraic geometry.
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\bibitem[MSTVA17]{MKSTVA}
Kelly McKinnie, Justin Sawon, Sho Tanimoto, and Anthony V\'arilly-Alvarado.
\newblock Brauer groups on {K}3 surfaces and arithmetic applications.
\newblock In {\em Brauer groups and obstruction problems}, volume 320 of {\em
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Kok~Onn Ng.
\newblock The classification of {$(3,3,3)$} trilinear forms.
\newblock {\em J. Reine Angew. Math.}, 468:49--75, 1995.

\bibitem[Nik79]{Nik}
V.~V. Nikulin.
\newblock Integer symmetric bilinear forms and some of their geometric
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\newblock {\em Izv. Akad. Nauk SSSR Ser. Mat.}, 43(1):111--177, 238, 1979.

\bibitem[Ran95]{Ran}
Ziv Ran.
\newblock Hodge theory and deformations of maps.
\newblock {\em Compositio Math.}, 97(3):309--328, 1995.

\bibitem[RS17]{RS17}
Francesco Russo and Giovanni Staglian\`o.
\newblock Congruences of 5-secant conics and the rationality of some admissible
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\newblock \texttt{ arXiv:1707.00999}.

\bibitem[RS18]{RS18}
Francesco Russo and Giovanni Staglian\`o.
\newblock Explicit rationality of some cubic fourfolds, 2018.
\newblock \texttt{ arXiv:1811.03502}.

\bibitem[Tei75]{Teissier}
B.~Teissier.
\newblock Introduction to equisingularity problems.
\newblock In {\em Algebraic geometry ({P}roc. {S}ympos. {P}ure {M}ath., {V}ol.
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\bibitem[vG05]{vanGeemen}
Bert van Geemen.
\newblock Some remarks on {B}rauer groups of {$K3$} surfaces.
\newblock {\em Adv. Math.}, 197(1):222--247, 2005.

\bibitem[Voi86]{Voisin86}
Claire Voisin.
\newblock Th\'eor\`eme de {T}orelli pour les cubiques de {${\bf P}^5$}.
\newblock {\em Invent. Math.}, 86(3):577--601, 1986.

\bibitem[Voi07]{voisin-book}
Claire Voisin.
\newblock {\em Hodge theory and complex algebraic geometry. {II}}, volume~77 of
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\newblock Cambridge University Press, Cambridge, english edition, 2007.
\newblock Translated from the French by Leila Schneps.

\bibitem[Voi13]{VoisinJAG}
Claire Voisin.
\newblock Abel-{J}acobi map, integral {H}odge classes and decomposition of the
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\newblock {\em J. Algebraic Geom.}, 22(1):141--174, 2013.

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