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↑ Catherine E. Housecroft, Alan G, Sharpe, Inorganic Chemistry, Pearson Prentice Hall; 2nd Edition, 2005, p. 29-33.
↑ Michael Munowitz, Principles of Chemistry, Norton & Company, 2000, p. 229-233.
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↑ Gagliardi, Laura; Roos, Björn O. (2005). Quantum chemical calculations show that the uranium molecule U2 has a quintuple bond. Nature 433: 848–851.
