%0 Journal Article %A Örn Arnaldsson %A Francis Valiquette %T Invariants of Surfaces in Three-Dimensional Affine Geometry %J Symmetry, integrability and geometry: methods and applications %D 2021 %V 17 %U http://geodesic.mathdoc.fr/item/SIGMA_2021_17_a32/ %G en %F SIGMA_2021_17_a32