1. [8]1 A. Grothendieck, Le groupe de Brauer. I. Algèbres d'Azumaya et interprétations diverses, Dix Exposés sur la Cohomologie des Schémas, North-Holland, Amsterdam, 1968, pp. 46–66.
2. [1] P. Deligne, Courbes elliptiques: formulaire d'après J. Tate, Modular functions of one variable, IV (Proc. Internat. Summer School, Univ. Antwerp, Antwerp, 1972), Springer, Berlin, 1975, 53–73. Lecture Notes in Math., Vol. 476.
3. [2] P. Deligne, J.-F. Boutot, L. Illusie, and J.-L. Verdier, Cohomologie Étale, Lecture Notes in Math., vol. 569, Springer-Verlag, Berlin, 1977.
4. [3] I. Dolgachev and M. Gross, Elliptic threefolds. I. Ogg-Shafarevich theory, J. Algebraic Geom. 3 (1994), no. 1, 39–80.
5. [4] A. Grassi, On minimal models of elliptic threefolds, Math. Ann. 290 (1991), no. 2, 287–301.