Gutiérrez, L., Erwin, P., Aladro, R., & Beckman, J. E. (2011). The outer disks of early-type galaxies - II. Surface-brightness profiles of unbarred galaxies and trends with Hubble type. Astronomical Journal, 142(5): 145, pp. 1-31. doi:10.1088/0004-6256/142/5/145.