Não informado. Publications of the Kapteyn Astronomical Laboratory at Groningen. University of Groningen.
Cita Chicago Style (17a ed.)Não informado. Publications of the Kapteyn Astronomical Laboratory at Groningen. Groningen, Holanda: University of Groningen.
Cita MLA (8a ed.)Não informado. Publications of the Kapteyn Astronomical Laboratory at Groningen. University of Groningen.
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