Analysis of 5p/sup 6/5d-(5p/sup 6/5f+5p/sup 6/6p+5p/sup 5/5d/sup 2/+5p/sup 5/5d6s) transitions in Tl XIII, Pb XIV and Bi XV and revised wavelengths for 5p/sup 6 1/S/sub 0/-5p/sup 5/5d(3/2, 5/2)/sub 1/ transitions in Hg XIII, Tl XIV, Pb XV, and Bi XVI