' The London School of Economics and Political Science 
(University of London) 
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London, WC2A 2AE 
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Department of Economics 
SG/JM 28th June, 1976. 
Professor Steindl, 
A-llo3, 
"ien Postfach 91, 
AUSTRIA. 
Dear Professor Steindl, 
My reaction to your letter of 13th June was, it appears,too quick and 
ill-founded. Over the weekend I was trying to reproduce my original discussion 
of the equation: 
I 
(1) + 
where a, b and h are all non-negative, and a < 1. Unfortunately, I could 
not find my notes with the discussion (of ten years ago!), so that I have had 
to do it again. However, the results are different than I thought they were. 
Let 1^ = E e^. On substituting to (1) we have 
= a + b |jL-e^J 
a + i a) 
(2) e 
Let X = a + i a). Since e 
(3) 
a 
= e (cos a) + i sin a)) , we have 
a , . , -ha , 
e cos a) = a + b- be cos h a) 
t a\ a , -ha 
(4) e sin a) = b e 
a i + h 
From Eq.4 e = (b sin h w/sin ai) S n (w) . Svibstituting into (3) gives 
—h 
(5) <f> (to) = n (u) cos a) + b n (w) cos h ai = a + b 
Continued.. 
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