... sample

Based on data obtained at TIRGO, Gornergrat, Switzerland.

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... (TIRGO

The Infrared Telescope at Gornergrat (Switzerland) is operated by CAISMI-CNR, Arcetri, Firenze.

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... NED

The NASA/IPAC Extragalactic Database (NED) is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the U.S. National Aeronautics and Space Administration.

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... DSS

The DSS was produced at the Space Telescope Science Institute under U.S. Government grant NAG W-2166.

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... Therefore

The intercept climbs from 0.95 to 1.10 if we adopt instead the scale of Wilson et al. (1972).

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...F

If the nearest objects, NGC 1569 and NGC 1156, are eliminated from the regression the significance becomes 4.0 $\sigma$. If, in addition, the reddest K-L value (IRAS 23365+3604) is eliminated, the significance becomes 2.1 $\sigma$.

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...K

If the object with the reddest K-L (IRAS 23365+3604) is eliminated from the regression, the significance becomes 2.4 $\sigma$.

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...

Although these galaxies were selected to be sufficiently distant, given the size of the IRAS beams compared to our ground-based photometry, aperture effects almost certainly contribute significantly to the scatter.

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...K

The red K-L cannot easily be attributed to nuclear activity, since LINERs tend to have NIR colors dominated by normal stellar populations (Lawrence et al. 1985).

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