Algebraic Bethe ansatz for integrable Kondo impurities in the   one-dimensional supersymmetric t-J model
  An integrable Kondo problem in the one-dimensional supersymmetric t-J model is studied by means of the boundary supersymmetric quantum inverse scattering method. The boundary $K$ matrices depending on the local moments of the impurities are presented as a nontrivial realization of the graded reflection equation algebras in a two-dimensional impurity Hilbert space. Further,the model is solved by using the algebraic Bethe ansatz method and the Bethe ansatz equations are obtained. 
H.-Q. Zhou and M.D. Gould