A. Liguori et M. Mintchev, SOME SOLUTIONS OF THE ZAMOLODCHIKOV TETRAHEDRON EQUATION, Journal of physics. A, mathematical and general, 26(17), 1993, pp. 887-891
By introducing a natural spectral parameter in the quantum Yang-Baxter
equation, we construct a family of solutions of Zamolodchikov's tetra
hedron equation. The general procedure is applied to the universal qua
ntum group R-matrix.