Level-rank duality of D-branes on the SU(N) group manifold
  The consequences of level-rank duality for untwisted D-branes on an SU(N) group manifold are explored. Relations are found between the charges of D-branes (which are classified by twisted K-theory) belonging to su(N)_K and su(K)_N WZW theories, in the case of odd N+K. An isomorphism between the charge algebras is also demonstrated in this case. 
Stephen G. Naculich and Howard J. Schnitzer