... observations

Table 3 is only available in in electronic form at http://www.aanda.org

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... Petrov

On leave from NVI, Inc.

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... rad

SI units are used throughout the paper. Conversion factors to non-standard units: $10^{-9}~{\rm rad} \approx 0.21~{\rm mas} \approx 14~\mu {\rm s}$.

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...(Dick & Richter 2004)

Available on the Internet at ftp://maia.usno.navy.mil/ser7/finals.all

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... gsf2006c

Available on the Web at
http://vlbi.gsfc.nasa.gov/solutions/2006c

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... and 2

Since component 3 was considered as a real value process, its spectral power at negative frequencies is the same as at positive frequencies.

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