• Judica Cordiglia Tecniche Applicate
• The Straight Dope: Were there really "Lost Cosmonauts" stranded in space?
• Aulis online
• Pietro.org
• Dr Sky
• For those who are interested in a diametrically opposed opinion to the one expressed in the present web site, we offer a link to James Oberg's article "Phantoms of Space"
  
• James Oberg returned to the issue of 'Lost Cosmonauts' in his book "Uncovering Soviet Disasters"
• Vladimir Ilyushin's Spaceflight, by Paul Tsarinsky
• Cosmonauts number Zero
• Grechko's encounter