1. W. Bruns, J. Gubeladze, and N.V. Trung, “Normal polytopes, triangulations, and Koszul algebras,” J. Reine Angew. Math. 485 (1997), 123–160.
2. W. Bruns, J. Gubeladze, and N.V. Trung, “Problems and algorithms for affine semigroups,” Semigroup Forum 64(2) (2002), 180–212.
3. W. Bruns and R. Koch, “Computing the integral closure of an affine semigroup, Effective methods in algebraic and analytic geometry, 2000 (Krakow),” Univ. Iagel. Acta Math. 39 (2001), 59–70. Software: Normaliz, ftp.mathematik.Uni-Osnabrueck.DE/pub/osm/kommalg/software.
4. R.T. Firla, private correspondence.
5. R.T. Firla and G.M. Ziegler, “Hilbert bases, unimodular triangulations, and binary covers of rational polyhedral cones,” Discrete Comp. Geom. 21 (1999), 205–216.