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M83	Morre, E. By     Atomic energy levels. As Derived From the Analyses of Optical Spectra [Текст]. The Spectra of Hydrogen, Deuterium, Tritium, Helium, Lithium, Beryllium, Boron, Carbon, Nitrogen, Oxygen, Fluorine, Neon, Sodium, Magnesium, Aluminum, Silicon, Phosphorus, Sulfur, Chlorine, Argon, Potassium, Calcium, Scandium, Titanium, and Vanadium / United states department of commerce, Cherles Sawyer, Secretary.National bureau of standards, E. U. Condon, Director. — 1949. — 309 p.