Notes.The full Table B.2 is available in electronic form at the CDS. A portion with only the 14 lowest frequency transitions is shown here for guidance regarding its form and content. Transitions are assigned with the rotational quantum numbers of the upper (first) and lower (second) levels. Observed frequencies are given. A “b” (seen in the full table) shows the b-type transitions. Transitions without “b” are of a-type. Sign “+” shows the blended transitions. An “e” shows the transitions observed but rejected from the fit as described in the text, because of the significant difference between observed and calculated frequencies; the observed minus calculated difference (Obs.-Calc.) is not given for these transitions.