Rotation curve model for NGC 1808. Top: an analytical model is built with five mass components: the stellar bulge and disk, the dark matter halo, the black hole, and the gaseous disk. The latter is included in the stellar disk. The contribution of each component is indicated as a dashed line. The blue symbols (stars) are adapted from the observations of Hα by Saikia et al. (1990) (average of the NW and SE sides) and the black triangles from the HI observations (Koribalski et al. 1993). Our CO rotation curve, corrected for bar perturbation, is indicated by the purple line. Bottom: derived frequencies Ω, Ω ± κ/2, indicating the Lindblad resonances, with the pattern speed of the bar highlighted in red.