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2. H. Dolezalek,A simple discussion on horizontal electric fields in the stratosphere as caused by tropospheric meteorological, or orographic features, Manuscript, 1969 A summary is given in this issue with the first paper.
3. R. E. Holzer andD. S. Saxon,Distribution of electrical conduction currents in the vicinity of thunderstorms, J. Geophys. Res.,57 (1952), 207?216.
4. F. S. Mozer andR. Serlin,Magnetospheric electric field measurements with balloons, J. Geophys. Res.74 (1969), 4739?4754.
5. D. Olson, private communication, 1969.