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en Julio Angel Fernández, Comets: nature, dynamics, origin, and their cosmogonical relevance, Springer Science & Business, Dordrecht 2005, ISBN 978-1-4020-3490-9, capitolul Comet contribution to the atmospheres of the terrestrial planets, Spre text online
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web.archive.org
en 2004, Primary Atmospheres (Astronomy 121: Lecture 14 Terrestrial Planet Atmospheres), Department of Physics University of Oregon, autor Dr. James Schombert Spre text onlineArhivat în , la Wayback Machine., consultat la 12 iunie 2011