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As part of an ongoing program of measuring galaxy redshifts at Mount Hopkins observatory, several previously unknown bright Seyfert galaxies have been discovered. Most of the objects are of Seyfert type 2, but several are type 1 objects where the broad permitted line region is easily visible only for the H-alpha line. The existence of such bright active galactic nuclei that have been overlooked in previous color or prism searches can have a large effect on the calculated number density of AGN.
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Huchra et al. (1982) studied this question.
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