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The IAU 2009 system of astronomical constants: the report of the IAU working group on numerical standards for Fundamental Astronomy [online]. aa.usno.navy.mil, 2011-07-10, [cit. 2018-11-05]. Dostupné online.DOI:10.1007/s10569-011-9352-4 Archivované 2016-12-27 z originálu. (po anglicky)
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