Liu Yunkang,Wu Ci-qian,Boundary value problems for composite systems of second order PDEs,J.Partial Ditterential Equation.

• 刘运康、吴兹潜；一类具有非负特征的双曲型偏微分方程组的边值问题；中山大学学报(自然科学)论丛；13(1988).