Spectral energy distribution of APM 08279+5255 (z=3.87) compared to the ultraluminous galaxies IRAS F10214+4724 (z=2.286), SMM 02399-0136 (z=2.8), and H1413+117 (z=2.558) (extracted from M. J. Irwin et al., ApJ, 505, 529). [tiff, 1.6M]