# Summary of domains of migration algorithms

 ${\displaystyle {\frac {\partial ^{2}P}{\partial x^{2}}}+{\frac {\partial ^{2}P}{\partial z^{2}}}-{\frac {1}{v^{2}(x,z)}}{\frac {\partial ^{2}P}{\partial t^{2}}}=0,}$ (12)