1. The Great Silence: the Science And Philosophy Of Fermi's Paradox;Milan,2018
2. If the universe is teeming with aliens... Where is everybody?;Webb,2002
3. The Fermi paradox is neither fermi's nor a paradox;Gray;Astrobiology,2015
4. The great silence-the controversy concerning extraterrestrial intelligent life;David Brin;Q. J. Roy. Astron. Soc.,1983
5. Fermi's paradox is a daunting problem—under whatever label;Milan;Astrobiology,2016