Hidden Symmetry of the Differential Calculus on the Quantum Matrix Space
  A standard bicovariant differential calculus on a quantum matrix space ${\tt Mat}(m,n)_q$ is considered. The principal result of this work is in observing that the $U_q\frak{s}(\frak{gl}_m\times \frak{gl}_n))_q$ is in fact a $U_q\frak{sl}(m+n)$-module differential algebra. 
S. Sinel'shchikov and L. Vaksman (Institute for Low Temperature   Physics and Engineering, Kharkov, Ukraine)