@article{01310578,
title = {Caustic of the three-dimensional ellipsoid. (Caustique de la surface ellipso\"\i dale \`a trois dimensions.)},
journal = {Experimental Mathematics},
volume = {8},
year = {1999},
pages = {49-55},
doi = {10.1080/10586458.1999.10504387},
zbl = {0951.53002},
language = {en},
url = {http://dml.mathdoc.fr/item/01310578}
}
Joets, Alain; Ribotta, Roland. Caustic of the three-dimensional ellipsoid. (Caustique de la surface ellipsoïdale à trois dimensions.). Experimental Mathematics, Tome 8 (1999) pp. 49-55. doi : 10.1080/10586458.1999.10504387. http://gdmltest.u-ga.fr/item/01310578/