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\noindent
Fig.1. Solutions of van der Pol's equation.
Results of a tabulation of the 28 order approximation in $\varepsilon$
for the different values of $\varepsilon$ are presented.

\begin{figure}
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\fbox{$\frac{d^{2}\chi}{dt^2} \ = \ - \chi + 
       \varepsilon^2 \ (1 - \chi^2) \ \frac{d\chi}{dt}$}

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