%0 Journal Article %A Filipe Kelmer %A Keti Tenenblat %T Superposition Formulae for the Geometric Bäcklund Transformations of the Hyperbolic and Elliptic Sine-Gordon and Sinh-Gordon Equations %J Symmetry, integrability and geometry: methods and applications %D 2024 %V 20 %U http://geodesic.mathdoc.fr/item/SIGMA_2024_20_a14/ %G en %F SIGMA_2024_20_a14