On generalized Besov and Triebel-Lizorkin spaces of regular   distributions
  We establish conditions on the parameters which are both necessary and sufficient in order that Besov and Triebel-Lizorkin spaces of generalized smoothness contain only regular distributions. We also connect this with the possibility of embedding such spaces in some particular Lebesgue spaces. 
Ant\'onio Caetano and Hans-Gerd Leopold
math.FA