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tokens: of the PA and inclination angle. Since the residual clumps proved to be not sensitive to the choices of the assumptions, we preferred the best fit model with PA major = 330° and i = 30°. The results from the kinematical analysis are presented in Fig. 6 , where the comparison between the model and the data in terms of intensity, velocity, and velocity dispersion maps (zeroth, first, and second moments, respectively) is shown. The model and data (smoothed by a factor of (2) are in excellent agreement. The kinematics of the molecular gas, traced by the CO(2–1) emission line, are clearly dominated by purely circular rotational motions around the nucleus. This is the first successful attempt to model the kinematics of the molecular gas in NGC 7213, thanks to the software 3D BAROLO, which is able to handle the available data, despite the sparse information that limited previous attempts to model the kinematics (e.g. Ramakrishnan et al. 2019 ). As is clearly visible in Fig. 7 , we found that the data cube central velocity was offset by an additional δV sys = 36 ± 10 km s −1 . This means that the systemic velocity of the source with respect to our rest frame has to be V sys = 1716 ± 10 km s −1 , which is a mean value between the systemic velocity obtained from the study of the stellar kinematics by Schnorr-Müller et al. (2014) , and the results by Ramakrishnan et al. (2019) . Fig. 7. PV diagrams on the major ( top panel ) and minor ( bottom panel ) axis, respectively. On the x -axis, the angular distance from the centre of the source along the direction fixed by the angle φ is reported. On the right y -axis, the velocity along the line of sight (in km s −1 ) is shown as it appears in the input data cube. On the left, the velocity along the line of sight (in km s −1 ) is shown, once the systemic velocity ( v sys = 36 ± 10 km s −1 ) has been subtracted. The data are represented in grey scales with blue contours, while the best fit model is identified by red contours. Upper panel : the blue circles represent the projected best fit rotational velocity at different radial distances from the centre, associated with each ring of the disc. Bottom panel : the signature of the potential outflow associated with Region C (bordered in green; see Sect. 4.3 ) is clearly visible as an excess of CO emission over 100 km s −1 with an offset of ∼1′′ from the centre of the rotation. Looking at the lower panels, the velocity dispersion in the best-fit model is ∼10−15 km s −1 : values that are expected from a rotation-dominated disc. The highest values of the velocity dispersion ( v disp ∼ 70 km s −1 ) are not reproduced by the best fit model. The high-dispersion residual clumps proved to be insensitive to our assumptions (e.g. PA, i , v rad ), therefore we suggest that the residuals are associated with non-rotational motion, as we discuss in Sect. 4.3 . 4.3. Complex structures in the CO emission The results of the modelling of the gas kinematics presented in Sect. 4.2