(Hopf) Algebra Automorphisms of the Hopf algebra ${\check U}^{\geq   0}_{r,s}({\mathfrak sl_{3}})$
  In this paper, we completely determine the group of algebra automorphisms for the two-parameter Hopf algebra ${\check U}_{r,s}^{\geq 0}({\mathfrak sl_{3}})$. As a result, the group of Hopf algebra automorphisms is determined for $\V$ as well. We further characterize all the derivations of the subalgebra $U^{+}_{r,s}({\mathfrak sl_{3})}$, and calculate its first degree Hochschild cohomology group. 
Xin Tang
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