Full paper in PDF:
$%S. N.   Melikhov, Generalized  fourier  expansions  for  distributions  and ultradistributions,
Rev. Mat. Complut. 12 (1999), no. 2, 349–379.%$
ABSTRACT
     Let  
     
 be  a  space  of  distributions  or  ultradistributions  of  Beurling
     type  on  the  
     
-dimensional  parallelepiped  
     
.  We
     investigate the following problems: 1) When can any element of 
     
 be
     expanded in absolutely convergent series in a system of generalized exponentials
     
 with special exponents 
     
, 
     
. 2) When can a sequence
     of the coefficients 
     
 in an expansion 
     
 be chosen
     so that it depends in a continuous and linear way on 
     
, where
     
 for all 
     
.
     
1991 Mathematics Subject Classification: 46F05,42C15.