@article{oai:nagoya.repo.nii.ac.jp:00020330, author = {SAO, Kazuo and KAMADA, Tetsuo}, journal = {Proceedings of the Research Institute of Atmospherics, Nagoya University}, month = {Mar}, pages = {109--111}, title = {Section 1. Propagation of Atmospherics and ELF Radio Noise}, volume = {19}, year = {1972} }