Results for mass models. Top panels: Two different mass models are fitted to the observed rotation curve (black squares): no bulge and fixed BH mass (A), bulge and fixed BH mass (B). The best-fitting model (solid black line) is the sum of the contributions from the stellar disc (dashed blue line), the cold gas disc (dotted green line), the BH (dotted purple line), and the stellar bulge (when present; dot-dashed red line). The different values of the rotation velocities in models A and B are due to different best-fitting values for the inclination: i = 38 ± 2° for model A and i = 26 ± 4° for model B. Bottom panels: Posterior distributions of the fitting parameters for models A and B.