David S. F. Portree, Humans to Mars: Fifty Years of Mission Planning, 1950 - 2000, NASA Monographs in Aerospace History Series, Number 21, February 2001. Available as NASA SP-2001-4521.
«Cópia arquivada». Consultado em 17 de dezembro de 2010. Arquivado do original em 13 de maio de 2013
searchmagazine.org
James C. McLane III, "One Way Ticket to Mars," SEARCH Magazine Jan/Feb 2009 linkArquivado em 5 de fevereiro de 2009, no Wayback Machine.
sff.net
Geoffrey A. Landis, "Footsteps to Mars: an Incremental Approach to Mars Exploration," Journal of the British Interplanetary Society, Vol. 48, pp. 367-342 (1995); presented at Case for Mars V, Boulder CO, 26–29 May 1993; appears in From Imagination to Reality: Mars Exploration Studies, R. Zubrin, ed., AAS Science and Technology Series Volume 91 pp. 339-350 (1997). (text available as Footsteps to Mars pdf file