Annals of the Astrophysical Observatory of the Smithsonian Institution (1900)
Washington : Government printing office · leaf 333
Annals Astrophysical Observatory, Volume IV. … Fig. 45. — General View from the West of Shuman Absorber, Tacony, 1911. Fig. 46. — General View from the South of Shuman-Boys Absorber, Meadi, 1913.
Infrared spectra · Solar radiation
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