Dieter Lutz, et al.
Max Planck-Institut f. extraterrestrische Physik, Postfach 1603 85740 Garching, GermanyWe will discuss ISO spectra of starburst galaxies, active galactic nuclei, and ultraluminous infrared galaxies, and use diagnostic SWS line ratios and PHT-S spectra to determine the energy source of ultraluminous galaxies