Prof. T.T. Moh, on his page on the Jacobian Conjecture, mentions that
"the classical Jacobian criteria for power series, implies that $k[[f(x,y),g(x,y) ]]=k[[x,y]]$. Thus we have $$x=F(f,g), y=G(f,g)$$ as power series. "
What is meant by the Jacobian Criteria for Power Series? Is there a good exposition of this?