On two rational difference equations

In this paper, we study the oscillating property of positive solutions and the global asymptotic stability of the unique equilibrium of the two rational difference equationsxn+1=xn+xn-1xn-2+axnxn-1+xn-2+a,n=0,1,2,…,andxn+1=xnxn-1+xn-2+axn-1+xnxn-2+a,n=0,1,2,…,where a is a nonnegative constant.