Blagojević, Pavle V. M., and Günter M. Ziegler. “Tetrahedra on Deformed and Integral Group Cohomology”. The Electronic Journal of Combinatorics 16, no. 2 (June 10, 2009): R16. Accessed March 27, 2026. https://www.combinatorics.org/ojs/index.php/eljc/article/view/v16i2r16.