718 
PONTIFICIAE ACADEMIAE SCIENTIARVM SCRIPTA VARIA - 28 
Naturally we have 
(111-3) 
(111-4, 
"oo 
| (4,9) dH =1 
0 
© A 
/ p(,9) dh =1 
0 
If primary input at instant (#- 6) but appearing at time ¢ 
is denoted by Pa db, then 
(111-5) 7, dO=Ru(t) ¢ (£, 8) d0=R.(t - 9) ¢ (£- 6, 0)d0 
whence 
(III-6) 
Ro) © (£, 0)=Ru(t-0) © (£- 6, 6) 
By definition we have 
111-7) 
R,(t)=R, (t-0)e Ls ra 
11] Allais - pag. 22