@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/