Rebekah et al. (21 de mayo de 2010). «Radial velocity planets de-aliased. A new, short period for Super-Earth 55 Cnc e». arXiv:1005,4050.
Andrew W. Howard, John Asher Johnson, Geoffrey W. Marcy, Debra A. Fischer, Jason T. Wright, Gregory W. Henry, Howard Isaacson, Jeff A. Valenti, Jay Anderson, Nikolai E. Piskunov (2010). «The NASA-UC Eta-Earth Program: II. A Planet Orbiting HD 156668 with a Minimum Mass of Four Earth Masses». arXiv:1003.3444v1 [astro-ph.EP].
