Maximum principles for a coupled system of second and fourth order elliptic equations and an application
The author deals with maximum principle for the linear system which associates with the system \[ \Delta^2 y= f_1(x, y,z)\quad\text{in }\Omega, \qquad -\Delta z= f_2(x,y,z)\quad\text{in }\Omega, \qquad y=\Delta y= z= 0\quad\text{on } \partial\Omega, \] where \(\Omega\) is a bounded domain in \(\mathbb R^n\).
scientific article; zbMATH DE number 2136131