$\begin{figure} \resizebox{\hsize}{!}{\includegraphics{1641_1.ps}} \end{figure}$

The light curves for the source 1641+399 (The same as Fig. 1 for the source 1641+399).

$\begin{figure} \resizebox{\hsize}{!}{\includegraphics{1641_2.ps}} \end{figure}$

Autocorrelation (ACF) and cross correlation (DCF) results for 1641+399 (The same as Fig. 2 for 1641+399).

$\begin{figure} \resizebox{\hsize}{!}{\includegraphics{1641_3.ps}} \end{figure}$

Modelling the light curve with exponential flares for 1641+399 (37 GHz) (The same as Fig. 3 for 1641+399 37 GHz).

$\begin{figure} \resizebox{\hsize}{!}{\includegraphics{1641_4.ps}} \end{figure}$

Modelling the light curve with eponential flares for 1641+399 (22 GHz) (The same as Fig. 3 for 1641+399 22 GHz).

$\begin{figure} \resizebox{\hsize}{!}{\includegraphics{1641_5.ps}} \end{figure}$

Optical flux level vs. phase $\Phi$ and flux of the model radio outbursts for 1641+399 (37 GHz) (The same as Fig. 4 for 1641+399 37 GHz).

$\begin{figure} \resizebox{\hsize}{!}{\includegraphics{1641_6.ps}} \end{figure}$

Optical flux level vs. phase $\Phi$ and flux of the model radio outbursts for 1641+399 (22 GHz) (The same as Fig. 4 for 1641+399 22 GHz).