On multiplicity problems for finite-dimensional representations of hyper   loop algebras
  Given a hyper loop algebra over a non-algebraically closed field, we address multiplicity problems in the underlying abelian tensor category of finite-dimensional representations. Namely, we give formulas for the l-characters of the simple objects, the Jordan-Holder multiplicities of the Weyl modules, and the Clebsch-Gordan coefficients. 
Dijana Jakelic and Adriano Moura