%0 Journal Article %A Maung Min-Oo %T Covariant vs Contravariant Methods in Differential Geometry %J Symmetry, integrability and geometry: methods and applications %D 2020 %V 16 %U http://geodesic.mathdoc.fr/item/SIGMA_2020_16_a94/ %G en %F SIGMA_2020_16_a94