SpacePDF

• NASA Facts – Viking Mission to Mars
  Jet Propulsion Laboratory, 1988, PDF, 36 KB
• Phobos: Close Encounter Imaging From the Viking Orbiters
  by T. C. Duxbury, J. D. Callahan & A. C. Ocampo, July 1984, PDF, 219.3 MB
• Spinoff 1976: A Bicentennial Report
  by Neil P. Ruzic, NASA SP-5121, April 1976, PDF, 21.4 MB. This annual review includes a description of the successful activities of the Viking Project.
• The Martian Landscape
  by The Viking Lander Imaging Team, NASA SP-425, 1978, Internet Archive, PDF, 281.3 MB
• The Viking mission to Mars
  by William R. Corliss, NASA SP-334, 1974, PDF, 23.3 MB
• Viking
  NASA News Release 75-42, February 1975, PDF, 5.1 MB
• Viking Encounter Press Kit
  by N. Panagakos & M. Parker, NASA News Release 76-103, June 1976, PDF, 7.0 MB
• Viking Orbiter Views of Mars
  by The Viking Orbiter Imaging Team (M. H. Carr et al.), NASA SP-441, 1980, Internet Archive, PDF, 53.4 MB
• Viking Press Kit
  by N. Panagakos & M. Parker, NASA News Release 75-183, June 1975, PDF, 5.8 MB