The analog of Trilinear Coordinates for Tetrahedra.
See also Tetrahedron, Trilinear Coordinates
References
Altshiller-Court, N. Modern Pure Solid Geometry. New York: Macmillan, 1935.
Mitrinovic, D. S.; Pecaric, J. E.; and Volenec, V. Ch. 19 in Recent Advances in Geometric Inequalities.
Dordrecht, Netherlands: Kluwer, 1989.
Woods, F. S. Higher Geometry: An Introduction to Advanced Methods in Analytic Geometry. New York: Dover, pp. 193-196, 1961.