Luyten W. J.
Physics , Theory of Relativity and GravitationOn Some Statistical Properties of Double Stars in Space I. A Formula for the Estimation of the Period in a Relatively Fixed System
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On Some Statistical Properties of Double Stars in Space. II. On the Mean Period of Double Stars in Space
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Technique , Aerospace EquipmentOn the Systematic and Accidental Errors of Modern Trigonometric Parallaxes
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