Examples of lifting the ambiguity on the ascending node for a visual binary. Top (cases 2, 5 of Table B.1): the slope of the computed curve is opposite to that of the V_r(B) − V_r(A) measurements: it is then necessary to add 180° to the values of Ω and ω given by the 6th Catalog of Orbits of Visual Binary Stars (6th COVBS; Hartkopf et al. 2001). Bottom (cases 3, 6 of Table B.1): the slope of the computed curve is opposite to that of V_r(A) measurements; there is no need to change the values of Ω and ω listed in the 6th COVBS.