M$\odot$. This galaxy clearly shows two dynamic components with quite similar rotation curves (plotted in Fig. 1 as C1 and C2, also see Amram et al. 2003). There are two points we would like to make about this galaxy. First, given the double kinematic component, we strongly suspect that this galaxy is probably the result of a merger of two similar-mass galaxies although we have no signs of this in the photometric profile of the object. In the T-F relation plotted in Fig. 4 we chose to represent this galaxy with the V$_{max}$ of the C1 component and the total B luminosity of the system as a whole. We, therefore, expect, in a naive scenario, that the galaxy will be higher in the T-F relation by at least 0.75 magnitudes, in addition to the amount of brightening due to star formation, if there is any, which, in turn, would explain why this galaxy lies above the T-F relation. The second point, which is related to the first, is that given our arbitrary choice to use only one component (C1) to represent a galaxy which clearly has two equally important kinematic structures, V$_{max}$ for HCG 91c is most probably an underestimate 