Tables 1-3 and the movie are only available in electronic form at http://www.aanda.org

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http://www.mpifr-bonn.mpg.de/div/vlbi/globalmm

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... $\delta$

$\delta=[\gamma(1-\beta \cos \phi)]^{-1}$ where $\gamma=(1-\beta^2)^{-1/2}$ is the Lorentz factor, $\beta$ is the speed in units of the speed of light and $\phi$ is the angle between the direction of the flow and the line of sight.

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... $\beta_{\rm {app}}$

$\beta_{\rm {app}}=(\beta \sin \phi)/(1-\beta \cos \phi)$ .

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