# The Green function for elliptic systems in two dimensions

I am reading some papers on Green functions of elliptic equations. Here the elliptic systems is stated as $$Lu=-\operatorname{div}(A\nabla u)$$ where $$A(y)=(a_{ij}^{\alpha\beta}(y))$$ is a matrix valued function in $$\mathbb{R}^{d}$$ and $$1\leq i,j\leq d$$, $$1\leq\alpha,\beta\leq m$$. I have read the paper named "The Green function estimates for Strongly elliptic systems of Second Order" and the paper dealt with the situation that the dimension $$d\geq 3$$. I want to know about the the case when $$d=2$$. Can you give me some references?