@article{oai:nipr.repo.nii.ac.jp:00001139,
 author = {Takahashi, Tadatoshi and Oya, Hiroshi and Yamagishi, Hisao},
 journal = {Memoirs of National Institute of Polar Research. Special issue},
 month = {Mar},
 note = {P(論文), Results of the electron number density obtained by the swept frequency impedance probe onboard the rockets launched at Syowa Station (69°00′S, 39°35′E) in the IMS period from 1977 to 1979 indicate that the ionization level of the polar ionosphere corresponds well to the precipitating particle flux. In the active aurora, a distinct stepwise structure 2∿3km in width across the magnetic field line corresponding to the edge of the auroral arc has been observed. The small-scale ionospheric structures with characteristic length of several kilometers are frequently observed as one of the characteristics of the auroral ionosphere.},
 pages = {283--299},
 title = {Observations of Electron Density in the Polar Ionosphere Using the Swept Frequency Impedance Probe},
 volume = {18},
 year = {1981}
}