[1] D. Gale: Neighboring vertices on a convex polyhedron. In: Linear inequalities and related systems. Princeton Univ. Press, Princeton 1956. MR 0085552 | Zbl 0072.37805
[2] B. L. v. d. Waerden: Algebra. 4. ed. Springer, Berlin-Göttingen-Heidelberg 1955. MR 0074354 | Zbl 0067.00502