Brard 



/. -X'(^',t') 



floi X'(T;',t ')-Lt 





with 



when (w/U)^, is continuous for t'>0. 

 Similarly, 



Oi(t') = p JJ yi(m, t') n(m) dS(m) 



with 



'i(m,t') = (g) ^ 7*(m,0+) + (^) ^ Syt(m,t') + J ^ (^) , Sy^Cm. t'-T')dT'. 



Hence: 



?;(t') = -PI^ (S) , JJ ri(m,0+) n(m) dSCm) 

 *' s 



^0 1 " 



"^ r J ^ (u) , ^^' If iP S>'i('"- t'-^') n(m) dS(m) . 

 "^ s 



In the case "aj," when (w/U)^, = (w/U)^^ M for t' >0, one has, at t' > 0, 

 a general resultant 



852 



