Suggestions for Further Reading 



Ezell, E. C; and Ezell, L. N.: On Mars: Exploration of the Red Planet, 

 1958-1978. NASA SP-4212, 1983. 



Klein, H. P.: The Viking Mission and the Search for Life on Mars. Rev. 

 Geophys. Space Phys., vol. 17, 1979, p. 1655. 



Billingham, J ., ed.: Life in the Universe. NASA CP-21 56, 1 981 . 



Wood, J. A.; and Chang, S., eds.: The Cosmic History of the Biogenic Ele- 

 ments and Compounds. NASA SP-476, 1985. 



Hartman, H.; Lawless, J. G.; and Morrison, P., eds.: Search for the Universal 

 Ancestors. NASA SP-477, 1985. 



Milne, D. H.; Raup, D. M.; Billingham, J.; Niklas, K.; and Padian, K., eds.: 

 The Evolution of Complex and Higher Organisms. NASA SP-478, 1 985. 



