Marcy, G. W., Isaacson, H., Howard, A. W., Rowe, J. F., Jenkins, J. M., Bryson, S. T., et al. (2014). Masses, Radii, and Orbits of Small Kepler Planets: The Transition from Gaseous to Rocky Planets. Astrophysical Journal, Suppl. Ser., 210: 20. doi:10.1088/0067-0049/210/2/20.