2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/58423One considers a special class of PDEs systems and one determines the associated symmetry group. Particulary, for the Blair system, one finds the symmetry group. A solutions of the Blair system gives a conformally flat contact metric structure and also it defines a "force-free" model of solar physics. By using the symmetry groups theory, one shows that the known solutions are group-invariant solutions and one gives new solutions.16 pagesMathematical PhysicsDifferential Geometry58G35, 35A30, 96.60.Htext