) = exp [— 2Dt wt — vt)21, 2I nt tve (2) where v = (log A) = fo°°dA log AII(A) and D = ((logA)2) — (logA)2. Expression (2) can be rewritten P(wt) vg--- rm tvrotvit eu(wdvi (3) with 1 IV 140 2Dt = log ert • (4) ( Since '(ive) is a slowly varying function of wt, this form shows that t