deletions | additions       diff --git a/introduction.tex b/introduction.tex  index 2fa3580..e692f1e 100644  --- a/introduction.tex  +++ b/introduction.tex 
...
com condi\c{c}\~oes de fronteiras de Dirichlet a expressão:  \begin{equation}  h(x,y,z) =   \sum^{\infty}_{n=0} \sum^{\infty}_{m=0}\{  exp \{  -2 \pi (k_x^2 +k_y^2)^1/2 +k_y^2)^{1/2}  \} A_{n}  \end{equation}