Linear continuous functionals on FN-type spaces
  By using the space of fuzzy numbers, in e.g. [5] have been considered several complete metric spaces (called here {\bf FN}-type spaces) endowed with addition and scalar multiplication, such that the metrics have nice properties but the spaces are not linear, i.e. are not groups with respect to addition and the scalar multiplication is not, in general, distributive with respect to usual scalar addition. This paper deals with the form of linear continuous functionals defined on these spaces. 
Sorin G. Gal
math.FA