Some new oscillation criteria for second order elliptic equations with damping
Rong-Kun Zhuang, Zheng‐an Yao · Annales Polonici Mathematici · 2005
Some new oscillation criteria are obtained for second order elliptic differential equations with damping $$\sum_{i,j=1}^nD_i[A_{ij}(x)D_jy]+\sum_{i=1}^nb_i(x)D_iy+q(x)f(y)=0,\ \quad x\in{\mit\Omega},$$ where ${\mit\Omega} $ is an exterior domain in $\math