Gibbs, Yvonne (August 12, 2015). "NASA Dryden Fact Sheet - Tu-144LL". NASA. Archived from the original on April 2, 2016. Retrieved February 7, 2016. NASA Dryden Tu-144 "Limited range and other technical problems led to service being discontinued in 1978 after only 102 passenger flights"
Gibbs, Yvonne (August 12, 2015). "NASA Dryden Fact Sheet - Tu-144LL". NASA. Archived from the original on April 2, 2016. Retrieved February 7, 2016. NASA Dryden Tu-144 "Limited range and other technical problems led to service being discontinued in 1978 after only 102 passenger flights"