Lise Meitner and O. R. Frisch Disintegration of Uranium by Neutrons: a New Type of Nuclear Reaction, Nature, Volume 143, Number 3615, 239-240 (11 February 1939).
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O. R. Frisch Physical Evidence for the Division of Heavy Nuclei under Neutron Bombardment, Nature, Volume 143, Number 3616, 276-276 (18 February 1939)Arxivat 23 de gener 2009 a Wayback Machine.
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O. R. Frisch Physical Evidence for the Division of Heavy Nuclei under Neutron Bombardment, Nature, Volume 143, Number 3616, 276-276 (18 February 1939)Arxivat 23 de gener 2009 a Wayback Machine.