2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/51586We review some contributions on fusion rules that were inspired by the work of Sharp, in particular, the generating-function method for tensor-product coefficients that he developed with Patera. We also review the Kac-Walton formula, the concepts of threshold level, fusion elementary couplings, fusion generating functions and fusion bases. We try to keep the presentation elementary and exemplify each concept with the simple $\su(2)_k$ case.harvmac 15 pages. Contribution to the Proceedings of the Workshop on symmetry in physics in memory of Robert T. SharpHigh Energy Physics - Theorytext