2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/226301We obtain the affine Euler-Poincaré equations by standard Lagrangian reduction and deduce the associated Clebsch-constrained variational principle. These results are illustrated in deriving the equations of motion for continuum spin systems and Kirchhoff's rod, where they provide a unified geometric interpretation.Submitted to Journal of Geometric Mechanics, 29 pages, no figuresChaotic Dynamicstext