Annals of the Astrophysical Observatory of the Smithsonian Institution (1900)
Washington : Government printing office · leaf 4
ANNALS OF THE ASTROPHYSICAL OBSERVATORY VOL. 7, PL. 1 Charles Greeley Abbot Director of the Astrophysical Observatory, 1907-1944. Secretary of the Smithsonian Institution, 1928-1944.
Infrared spectra · Solar radiation
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