Kingsley, S. The Search for Extraterrestrial Intelligence (SETI) in the Optical Spectrum. SPIE Digital Library.
Chicago-viite (17. p.)Kingsley, Stuart. The Search for Extraterrestrial Intelligence (SETI) in the Optical Spectrum. SPIE Digital Library.
MLA-viite (8. p.)Kingsley, Stuart. The Search for Extraterrestrial Intelligence (SETI) in the Optical Spectrum. SPIE Digital Library.
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