References 1) W. Alvarez “T-Rex And the Crater of Doom”
2) H.J. Melosh “Impact Cratering. A Geological Process”
3) W. Hartmann “1908 Siberian Explosion”
4) V. L. Masaitis “Review of the Barringer’s Crater Studies and Views on the Crater’s Origin”
5)Wikipedia, the free encyclopedia
6)Planetary Science Institute website