Observation of a Line in the Galactic Radio Spectrum: Radiation from Galactic Hydrogen at 1,420 Mc./sec.

@article{Ewen1951ObservationOA,
  title={Observation of a Line in the Galactic Radio Spectrum: Radiation from Galactic Hydrogen at 1,420 Mc./sec.},
  author={Harold I. Ewen and Edward M. Purcell},
  journal={Nature},
  year={1951},
  volume={168},
  pages={356-356}
}
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