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Completion of long-term astrometric plate series yields revised results on the orbits and parallaxes. The subdwarf 'i Cassiopeiae seems to be overluminous; the distance of the supergiant 6 Aurigae is near 600 pc. The unresolved companion in the red dwarf pair BD +6°398 is of very low mass, and the companion of BD +67°552 massive but probably underluminous.
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Wulff D. Heintz (1972) studied this question.
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