Prime Gamma Rings with Centralizing and Commuting Generalized   Derivations
  Let $M$ be a prime $\Gamma$-ring satisfying a certain assumption and $D$ a nonzero derivation on $M$. Let $f:M\rightarrow M$ be a generalized derivation such that $f$ is centralizing and commuting on a left ideal $J$ of $M$. Then we prove that $M$ is commutative. 
Md Fazlul Hoque and A C Paul
math.AC math.RA