Much of the geometry code in Octave is based on the Qhull
library^{12}.
Some of the documentation for Qhull, particularly for the options that
can be passed to `delaunay`

, `voronoi`

and `convhull`

,
etc., is relevant to Octave users.

Barber, C.B., Dobkin, D.P., and Huhdanpaa, H.T., The Quickhull Algorithm for Convex Hulls, ACM Trans. on Mathematical Software, 22(4):469–483, Dec 1996, http://www.qhull.org