@article{00767403, title = {Polarity of embedded and circumscribed ellipsoids.}, journal = {Beitr\"age zur Algebra und Geometrie}, volume = {36}, year = {1995}, pages = {17-24}, zbl = {0819.52007}, language = {en}, url = {http://dml.mathdoc.fr/item/00767403} }
Juhnke, Friedrich. Polarity of embedded and circumscribed ellipsoids.. Beiträge zur Algebra und Geometrie, Tome 36 (1995) pp. 17-24. http://gdmltest.u-ga.fr/item/00767403/