Comparison between different 3D kinematical models and the observations. Top: position–velocity diagrams at a resolution of both 2′′ and 5′′. The slices are taken along the major and minor axes, as indicated in Fig. 4 (left). Contours are at  − 1.5 (dashed), 1.5, 3, 6, 12  ×  σ. Bottom: channel maps at 2′′ resolution (red contours) superimposed with two models: differential rotation (black-solid contours) and solid body rotation (black-dashed contours). Contours are at 2σ. The cross marks the galaxy centre. The circle shows the beam size. See text for details.