I am searching some libraries or toolboxes (preferred MATLAB) for solving acoustic wave equation in heterogeneous media with time varying source term, i.e. $$\nabla^2 \psi(\vec{r},t) - \frac{1}{c(\vec{r})^2} \frac{\partial^2}{\partial t^2}\psi(\vec{r},t) = s(\vec{r},t)$$
Actually I want to verify the k-Wave toolbox I modified, which solves another version of the above equation, by using some other softwares, so are there any other recommendations other than k-Wave? Thanks!