Key points are not available for this paper at this time.
Of 90 extragalactic objects chosen from the I RAS catalog on the basis of brightness at 60 m and "warm" infrared color f.(25 m)lfv(60 m) > 0.2, 12 have luminosities characteristic of quasars. These 12 ultraluminous objects have Seyfert spectra, and nine of them show morphological evidence for recent collisions or mergers-they plausibly represent a transition stage between cooler ultraluminous infrared galaxies and optical quasars.
Sanders et al. (Sun,) studied this question.