$$ \newcommand{\tp}{\thinspace .} $$

Bibliography

  1. H. P. Langtangen. Finite difference methods for wave motion, http://tinyurl.com/k3sdbuv/pub/wave.
  2. H. P. Langtangen. Scaling of Differential Equations, 2015, http://tinyurl.com/qfjgxmf/web.