guide for observations of phenomena
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Observ. Number Type Site of Download Available
of observations of observation Reference files as
period for satellites observ. standard
J1 J2 J3 J4 content data data
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1836-1972 4411 obs. OC x 45 sites Fairhead et al (1986) Content Data no
1652-1983 16802 obs. EC x 426 sites Lieske (1986a and 1986b) Content Data no
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