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@article{CM_1984__52_2_231_0, author = {Im Hof, Hans-Christoph}, title = {Ellipsoids and hyperboloids with infinite foci}, journal = {Compositio Mathematica}, pages = {231--244}, publisher = {Martinus Nijhoff Publishers}, volume = {52}, number = {2}, year = {1984}, mrnumber = {750359}, zbl = {0544.53034}, language = {en}, url = {http://geodesic.mathdoc.fr/item/CM_1984__52_2_231_0/} }
Im Hof, Hans-Christoph. Ellipsoids and hyperboloids with infinite foci. Compositio Mathematica, Tome 52 (1984) no. 2, pp. 231-244. http://geodesic.mathdoc.fr/item/CM_1984__52_2_231_0/